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# Hydrology
## Themes
The central theme of hydrology is that water circulates throughout the Earth through different pathways and at different rates. The most vivid image of this is in the evaporation of water from the ocean, which forms clouds. These clouds drift over the land and produce rain. The rainwater flows into lakes, rivers, or aquifers. The water in lakes, rivers, and aquifers then either evaporates back to the atmosphere or eventually flows back to the ocean, completing a cycle. Water changes its state of being several times throughout this cycle.
The areas of research within hydrology concern the movement of water between its various states, or within a given state, or simply quantifying the amounts in these states in a given region. Parts of hydrology concern developing methods for directly measuring these flows or amounts of water, while others concern modeling these processes either for scientific knowledge or for making a prediction in practical applications.
### Groundwater
Ground water is water beneath Earth\'s surface, often pumped for drinking water. Groundwater hydrology (hydrogeology) considers quantifying groundwater flow and solute transport. Problems in describing the saturated zone include the characterization of aquifers in terms of flow direction, groundwater pressure and, by inference, groundwater depth (see: aquifer test). Measurements here can be made using a piezometer. Aquifers are also described in terms of hydraulic conductivity, storativity and transmissivity. There are a number of geophysical methods for characterizing aquifers. There are also problems in characterizing the vadose zone (unsaturated zone).
### Infiltration
Infiltration is the process by which water enters the soil. Some of the water is absorbed, and the rest percolates down to the water table. The infiltration capacity, the maximum rate at which the soil can absorb water, depends on several factors. The layer that is already saturated provides a resistance that is proportional to its thickness, while that plus the depth of water above the soil provides the driving force (hydraulic head). Dry soil can allow rapid infiltration by capillary action; this force diminishes as the soil becomes wet. Compaction reduces the porosity and the pore sizes. Surface cover increases capacity by retarding runoff, reducing compaction and other processes. Higher temperatures reduce viscosity, increasing infiltration.
### Soil moisture {#soil_moisture}
Soil moisture can be measured in various ways; by capacitance probe, time domain reflectometer or tensiometer. Other methods include solute sampling and geophysical methods.
### Surface water flow {#surface_water_flow}
Hydrology considers quantifying surface water flow and solute transport, although the treatment of flows in large rivers is sometimes considered as a distinct topic of hydraulics or hydrodynamics. Surface water flow can include flow both in recognizable river channels and otherwise. Methods for measuring flow once the water has reached a river include the stream gauge (see: discharge), and tracer techniques. Other topics include chemical transport as part of surface water, sediment transport and erosion.
One of the important areas of hydrology is the interchange between rivers and aquifers. Groundwater/surface water interactions in streams and aquifers can be complex and the direction of net water flux (into surface water or into the aquifer) may vary spatially along a stream channel and over time at any particular location, depending on the relationship between stream stage and groundwater levels.
### Precipitation and evaporation {#precipitation_and_evaporation}
In some considerations, hydrology is thought of as starting at the land-atmosphere boundary and so it is important to have adequate knowledge of both precipitation and evaporation. Precipitation can be measured in various ways: disdrometer for precipitation characteristics at a fine time scale; radar for cloud properties, rain rate estimation, hail and snow detection; rain gauge for routine accurate measurements of rain and snowfall; satellite for rainy area identification, rain rate estimation, land-cover/land-use, and soil moisture, snow cover or snow water equivalent for example.
Evaporation is an important part of the water cycle. It is partly affected by humidity, which can be measured by a sling psychrometer. It is also affected by the presence of snow, hail, and ice and can relate to dew, mist and fog. Hydrology considers evaporation of various forms: from water surfaces; as transpiration from plant surfaces in natural and agronomic ecosystems. Direct measurement of evaporation can be obtained using Simon\'s evaporation pan.
Detailed studies of evaporation involve boundary layer considerations as well as momentum, heat flux, and energy budgets.
### Remote sensing {#remote_sensing}
thumb\|upright=1.3\|Estimates of changes in water storage around the Tigris and Euphrates Rivers, measured by NASA\'s GRACE satellites. The satellites measure tiny changes in gravitational acceleration, which can then be processed to reveal movement of water due to changes in its total mass. *Main article: Remote sensing* Remote sensing of hydrologic processes can provide information on locations where *in situ* sensors may be unavailable or sparse. It also enables observations over large spatial extents. Many of the variables constituting the terrestrial water balance, for example surface water storage, soil moisture, precipitation, evapotranspiration, and snow and ice, are measurable using remote sensing at various spatial-temporal resolutions and accuracies. Sources of remote sensing include land-based sensors, airborne sensors and satellite sensors which can capture microwave, thermal and near-infrared data or use lidar, for example.
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# Hydrology
## Themes
### Water quality {#water_quality}
In hydrology, studies of water quality concern organic and inorganic compounds, and both dissolved and sediment material. In addition, water quality is affected by the interaction of dissolved oxygen with organic material and various chemical transformations that may take place. Measurements of water quality may involve either in-situ methods, in which analyses take place on-site, often automatically, and laboratory-based analyses and may include microbiological analysis.
### Integrating measurement and modelling {#integrating_measurement_and_modelling}
- Budget analyses
- Parameter estimation
- Scaling in time and space
- Data assimilation
- Quality control of data -- see for example Double mass analysis
### Prediction
Observations of hydrologic processes are used to make predictions of the future behavior of hydrologic systems (water flow, water quality). One of the major current concerns in hydrologic research is \"Prediction in Ungauged Basins\" (PUB), i.e. in basins where no or only very few data exist.
### Statistical hydrology {#statistical_hydrology}
The aims of Statistical hydrology is to provide appropriate statistical methods for analyzing and modeling various parts of the hydrological cycle. By analyzing the statistical properties of hydrologic records, such as rainfall or river flow, hydrologists can estimate future hydrologic phenomena. When making assessments of how often relatively rare events will occur, analyses are made in terms of the return period of such events. Other quantities of interest include the average flow in a river, in a year or by season.
These estimates are important for engineers and economists so that proper risk analysis can be performed to influence investment decisions in future infrastructure and to determine the yield reliability characteristics of water supply systems. Statistical information is utilized to formulate operating rules for large dams forming part of systems which include agricultural, industrial and residential demands.
### Modeling
*Main article: Hydrological modeling* Hydrological models are simplified, conceptual representations of a part of the hydrologic cycle. They are primarily used for hydrological prediction and for understanding hydrological processes, within the general field of scientific modeling. Two major types of hydrological models can be distinguished:
- Models based on data. These models are black box systems, using mathematical and statistical concepts to link a certain input (for instance rainfall) to the model output (for instance runoff). Commonly used techniques are regression, transfer functions, and system identification. The simplest of these models may be linear models, but it is common to deploy non-linear components to represent some general aspects of a catchment\'s response without going deeply into the real physical processes involved. An example of such an aspect is the well-known behavior that a catchment will respond much more quickly and strongly when it is already wet than when it is dry.
- Models based on process descriptions. These models try to represent the physical processes observed in the real world. Typically, such models contain representations of surface runoff, subsurface flow, evapotranspiration, and channel flow, but they can be far more complicated. Within this category, models can be divided into conceptual and deterministic. Conceptual models link simplified representations of the hydrological processes in an area, whereas deterministic models seek to resolve as much of the physics of a system as possible. These models can be subdivided into single-event models and continuous simulation models.
Recent research in hydrological modeling tries to have a more global approach to the understanding of the behavior of hydrologic systems to make better predictions and to face the major challenges in water resources management.
### Transport
Water movement is a significant means by which other materials, such as soil, gravel, boulders or pollutants, are transported from place to place. Initial input to receiving waters may arise from a point source discharge or a line source or area source, such as surface runoff. Since the 1960s rather complex mathematical models have been developed, facilitated by the availability of high-speed computers. The most common pollutant classes analyzed are nutrients, pesticides, total dissolved solids and sediment.
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# Hydrology
## Organizations
### Intergovernmental organizations {#intergovernmental_organizations}
- International Hydrological Programme (IHP)
### International research bodies {#international_research_bodies}
- International Water Management Institute (IWMI)
- UN-IHE Delft Institute for Water Education
### National research bodies {#national_research_bodies}
- Centre for Ecology and Hydrology -- UK
- Centre for Water Science, Cranfield University, UK
- eawag -- aquatic research, ETH Zürich, Switzerland
- Institute of Hydrology, Albert-Ludwigs-University of Freiburg, Germany
- United States Geological Survey -- Water Resources of the United States
- NOAA\'s National Weather Service -- Office of Hydrologic Development, US
- US Army Corps of Engineers Hydrologic Engineering Center, US
- Hydrologic Research Center, US
- NOAA Economics and Social Sciences, United States
- University of Oklahoma Center for Natural Hazards and Disasters Research, US
- National Hydrology Research Centre, Canada
- National Institute of Hydrology, India
### National and international societies {#national_and_international_societies}
- American Institute of Hydrology (AIH)
- Geological Society of America (GSA) -- Hydrogeology Division
- American Geophysical Union (AGU) -- Hydrology Section
- National Ground Water Association (NGWA)
- American Water Resources Association
- Consortium of Universities for the Advancement of Hydrologic Science, Inc. (CUAHSI)
- International Association of Hydrological Sciences (IAHS)
- Statistics in Hydrology Working Group (subgroup of IAHS)
- German Hydrological Society (DHG: Deutsche Hydrologische Gesellschaft)
- Italian Hydrological Society (SII-IHS) -- [Società Idrologica Italiana](http://www.sii-ihs.it)
- Nordic Association for Hydrology
- British Hydrological Society
- Russian Geographical Society (Moscow Center) -- Hydrology Commission
- International Association for Environmental Hydrology
- International Association of Hydrogeologists
- [Society of Hydrologists and Meteorologists -- Nepal](http://soham.org.np/)
### Basin- and catchment-wide overviews {#basin__and_catchment_wide_overviews}
- Connected Waters Initiative, University of New South Wales -- Investigating and raising awareness of groundwater and water resource issues in Australia
- Murray Darling Basin Initiative, Department of Environment and Heritage, Australia
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# Hydrology
## Research journals {#research_journals}
- [*International Journal of Hydrology Science and Technology*](http://www.inderscience.com/jhome
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# Horace Engdahl
**Horace Oscar Axel Engdahl** (born 30 December 1948) is a Swedish literary historian and critic, and has been a member of the Swedish Academy since 1997. He was the permanent secretary of the Swedish Academy from 1999 to June 2009, when he was succeeded by Swedish author and historian Peter Englund.
## Biography
Engdahl was born in Karlskrona, Blekinge, Sweden. He earned his B.A. in 1970 at Stockholm University; he earned his doctoral degree (PhD) in 1987, with a study on Swedish romanticism, but had meanwhile been active as a literary critic, translator and journal editor, and was one of the introducers of the continental tradition of literary scholarship in Sweden. He is adjunct professor of Scandinavian Literature at the University of Aarhus in Denmark. He speaks Swedish, English, German, French and Russian fluently.
Engdahl was member of the *Kris* editorial staff.
On 16 October 1997, Engdahl became a member of the Swedish Academy, elected to seat number 17 vacated by the death of Johannes Edfelt; on 1 June 1999, he succeeded Sture Allén as the Academy\'s permanent secretary, i.e. its executive member and spokesperson. As such, he had the annual task of announcing the recipient of the Nobel Prize in Literature to the public. On 20 December 2008 it was announced that after ten years Engdahl would step down as the Academy\'s permanent secretary on 1 June 2009.
Between 1989 and 2014 he was married to Ebba Witt-Brattström, professor of literature at Södertörn University outside Stockholm. They have three sons.
## Controversy
In October 2008, Engdahl told the *Associated Press* that the United States is \"too isolated, too insular\" to challenge Europe as \"the center of the literary world\" and that \"they don\'t translate enough and don\'t really participate in the big dialogue of literature \...That ignorance is restraining.\" At the time of the interview, no American author had received a Nobel Prize in Literature since 1993. His comments generated controversy across the Atlantic, with Harold Augenbraum, head of the U.S. National Book Foundation offering to send him a reading list.
In April 2018, the *New York Times* reported that Engdahl had railed against former Academy members who left following allegations of sexual abuse by Jean-Claude Arnault
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# House of Pain
**House of Pain** was an American hip hop trio that released three albums in the 1990s. The group consisted of DJ Lethal, Danny Boy, and Everlast. They are best known for their 1992 hit single \"Jump Around\", which reached number 3 in their native United States of America, number 6 in Ireland and number 8 in the United Kingdom. The group broke up in 1996.
Lead rapper Everlast went on to pursue a solo career as a blues rock artist and member of the supergroup La Coka Nostra which also featured DJ Lethal. DJ Lethal would later join and find commercial success with the rap rock band Limp Bizkit. House of Pain reunited briefly in 2010 for a world tour.
The group\'s name is a reference to the H.G. Wells novel *The Island of Dr Moreau*, a reference carried further by the naming of their 2011 tour *He Who Breaks the Law*; however, they initially became aware of the phrase via the Oingo Boingo song \"No Spill Blood\", of which they were fans.
## Band history {#band_history}
### 1990--1992: Formation and breakthrough {#formation_and_breakthrough}
In 1990, Daniel O\'Connor (Danny Boy O\'Connor) got together with fellow rapper Erik Schrody (Everlast) who had just released a rap album called *Forever Everlasting* (1990), that did not have much success. O\'Connor knew Schrody when he went to William Howard Taft High School in Woodland Hills, California (1984--1986), and various hip hop events they attended in their teens. Both of Irish American descent, they decided to make a hip hop group with this identity. While hanging out at O\'Connor\'s home, Schrody noticed a cassette with the title *House of Pain*, which was a demo of a Punk group O\'Connor tried to put together. Schrody really liked the name and felt they should re-use as their name. Schrody brought in his former DJ Leor Dimant (DJ Lethal), who is of Latvian descent, and House of Pain was created. Schrody would become the lead rapper, while O\'Connor acted as the hype man, second emcee, art director and the graphic artist of the group. After they recorded a demo, for which O\'Connor designed the cover, that created a bidding war among labels. The label they chose was Tommy Boy Records, who credited O\'Connor\'s art work with having initially caught their attention.
In 1992, they released their debut album *House of Pain*, subtitled *Fine Malt Lyrics.* Their first single \"Jump Around\" was a major hit. In the United States, it peaked at number 3 on the *Billboard* Hot 100, while reaching number 5 on the Hot Rap Songs, 13 on Rhythmic Top 40, 1 on Hot Dance Music/Maxi-Singles Sales, number 17 on the *Billboard* Dance Club Songs, and is certified platinum. The song was produced by Lawrence Muggerud (DJ Muggs) and performed by Schrody. Both Muggerud and Schrody knew each other since Rhyme Syndicate. Muggerud who had a beat he had submitted to various artist, eventually invited Schrody to give it a try. Schrody wrote lyrics in his driveway and being influenced by dance hall singer Shabba Ranks part of the lyrics were \"Jump around, if you love freedom. Jump around, if you love culture\", which Muggerud suggested they trim down to \"Jump Around\". While re-working his lyrics, Muggerud came up with the iconic horn that accompany the song. Their second single \"Shamrocks and Shenanigans (Boom Shalock Lock Boom)\" peaked at 65 on the *Billboard* Hot 100, 75 on the Hot R&B/Hip-Hop Songs, 14 on the Dance Club Songs, and 74 on Radio Songs. The album peaked at 14 on the *Billboard* 200, 14 on the U.S. *Billboard* Top Current Albums, 16 on the U.S. *Billboard* Top R&B/Hip-Hop Albums, 14 on the U.S. *Billboard* Top Album Sales, and is certified platinum.
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# House of Pain
## Band history {#band_history}
### 1993--1996: Subsequent success and group\'s breakup {#subsequent_success_and_groups_breakup}
In 1993, they were among the rap artists who had cameo roles in Ted Demme\'s film *Who\'s the Man?*. For this project they provided a theme song by the same name, which was also used as a single for the soundtrack and their subsequent album. It rose to number 97 on the *Billboard* Hot 100, 77 on the Hot R&B/Hip-Hop Singles & Tracks, and 10 on the US *Billboard* Hot Dance Music/Maxi-Singles Sales. Also that year, they participated together with Helmet, along with several other rap acts, on the 1993 rap rock collaborative *Judgment Night* film soundtrack.
In 1994, they released *Same as It Ever Was*. The album peaked at 12 equally on the *Billboard* 200, the U.S. *Billboard* Top Current Albums, the U.S. *Billboard* Top R&B/Hip-Hop Albums, the U.S. *Billboard* Top Album Sales, and is certified gold. *AllMusic* gave it four out five stars. Matt Carlson of *The Michigan Daily* found the album quite good and noted \"the music is laid back with some heavy driving forces underlying and strengthening it\". J.D. Constantine of *The Baltimore Sun* did not like album and found it monotonous and unimaginative. Roger Catlin of the *Hartford Courant* said that while finding the continuity monotonous it\'s \"hard and compelling\" as well as a \"strong outing\". Andrew Love of *The Ocala Star-Banner* gave it four stars saying \"this is a band that has definitely progressed over the course of one album\". Music critic Robert Christgau, who did not like their previous and subsequent album, gave it an A− and described it as \"the hardest hip hop of the year\".
In 1996, they released *Truth Crushed to Earth Shall Rise Again*. The album peaked at 47 on the *Billboard* 200, 47 on the U.S. *Billboard* Top Current Albums, 31 on the U.S. *Billboard* Top R&B/Hip-Hop Albums, and 47 on the U.S. *Billboard* Top Album Sales. At the release party, Schrody decided to disband the group. Sputnikmusic wrote that \"the trio's most rounded, consistent & memorable LP is grossly under-appreciated.\" Dave Ferman of the *Fort Worth Star-Telegram* gave it one star and a half, calling it a \"woeful mess\". Steve Juon of *RapReviews* gave it a seven out of ten. *AllMusic* music gave it two point five stars out of five.
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# House of Pain
## Band history {#band_history}
### 1997--present day: solo projects and reunions {#present_day_solo_projects_and_reunions}
From then on, the members continued their separate careers. Schrody achieved multi-platinum solo fame in 1998 with his album *Whitey Ford Sings the Blues,* where he developed a style that blended rap with acoustic guitar, as well as singing.
Dimant became the DJ of multi-platinum nu metal band Limp Bizkit.
O\'Connor, did some freelance work designing clothes, and was involved in several music projects.
In late 2004, the creation of the rap supergroup La Coka Nostra started when O\'Connor was mentoring young artists. He took notice of two up and comers which included George Carroll (Slaine) and brought them to meet his former DJ from House of Pain, Leor Dimant, who at the time was working on a compilation album and championing a new artist as well. They decided to make a group and asked O\'Connor to become a member as a hype man and art director. After accepting, O\'Connor felt that there was a void and asked experienced rapper William Braunstein (Ill Bill) to join. The group\'s name came about, when O\'Connor teased Carroll and Braunstein with that nickname, after they both had a night out. The group started releasing music on MySpace, and went viral. Eventually, O\'Connor received a letter from former House of Pain colleague Erik Schrody, who asked if he could join. By 2006, the group consisted of O\'Connor, Carroll, Dimant, Braunstein, and Schrody.
In 2009, La Coka Nostra released *A Brand You Can Trust* was released on July 14, 2009, on Suburban Noize Records. It sold over 500,000 units. *AllMusic* gave four out of five stars. Andrew Kameka of *HipHopDX* wrote that \"the album is a mostly solid effort and exactly what someone would expect from a supergroup of like-minded members known for high-energy music\". Adam Kennedy of the *BBC* while praising some the moments of the album said \"it's a tantalising parting taste of potential capabilities, yet until they improve a customer satisfaction hit rate that barely troubles one in three tunes here\". Steve Juon of *RapReviews* gave it a seven out of ten. *Sputnikmusic* described it as \"a disjointed effort, but still pretty decent in and of itself and gave it three point five out of five. Thomas Quinlan of *Exclaim!* said \"La Coka Nostra are an interesting collection of collaborators that live up to the hype\".
On March 2, 2012, it was announced that Schrody would be leaving La Coka Nostra due to his daughter\'s medical issues, while O\'Connor and Dimant pursued two more project with the group *Masters of the Dark Arts* (2012) and *To Thine Own Self Be True* (2016).
House of Pain reunited at a private event held by UFC president Dana White in Boston on St. Patrick\'s Day 2009. It was officially announced on August 10, 2010, that House of Pain had reunited and performed their first \"official\" show in a decade at the second annual Epicenter music festival in Fontana, California, on September 25, 2010. Though Dimant is still a member of the group, he did not join them on their 2011 reunion tour due to prior obligations with Limp Bizkit. In April--May 2011 House of Pain attended the Groovin\' the Moo touring festival in Australia, and also performed at Scotland\'s T in the Park festival on July 9, 2011, as well as Sonisphere UK Festival on July 12 of the same year.
House of Pain reunited in 2017 for a 25th Anniversary Tour. The tour included shows in DC, Ohio, Pennsylvania, New York, Massachusetts, and California.
Between reunions and projects together, Schrody continues with his solo career, while Dimant still works with Limp Bizkit, and in 2019 O\'Connor opened The Outsiders House Museum dedicated to both the novel and the film *The Outsiders*
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# Harald Tveit Alvestrand
**Harald Tveit Alvestrand** (born 29 June 1959) is a Norwegian computer scientist. He was chair of the Internet Engineering Task Force (IETF) from 2001 until 2005, succeeding Fred Baker. Within the IETF, Alvestrand was earlier the chair of the Areas for Applications from 1995 until 1997, and of Operations and Management in 1998.
## Biography
Alvestrand was born in Namsos, Norway, received his education from Bergen Cathedral School and the Norwegian Institute of Technology, and has worked for Norsk Data, UNINETT, EDB Maxware, Cisco Systems, and Google.
He is an author of several important Request for Comments (RFCs), many in the general area of Internationalization and localization, most notable the documents required for interoperability between SMTP and X.400. Since the start of the use of OIDs he has run a front end to the hierarchy of assignments according to X.208.
At the end of 2007 Alvestrand was selected for the ICANN Board, where he remained until December 2010. In 2001 he became a member of the Unicode Board of Directors. He was a co-chair of the IETF EAI and USEFOR WGs.
Harald Alvestrand was the executive director of the Linux Counter organization. He was a member of the Norid Board, and the RFC Independent Submissions Editorial Board. `{{As of|2008}}`{=mediawiki} he lived in Trondheim, Norway, and has been working for Google since 2006.
## Publications
### Best Current Practices {#best_current_practices}
-
-
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### Other important RFCs {#other_important_rfcs}
-
- This memo prepared the UTF-8 50-years plan in `{{IETF RFC|2277|link=no}}`{=mediawiki}.
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- (With co-author John Klensin
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# Hezârfen Ahmed Çelebi
**Hezârfen Ahmed Çelebi** (*lit=Polymath Ahmed the wise*; 1609 -- 1640) was an Ottoman scientist, inventor, chemist, astronomer, physician, Andalusi musician, and poet from Istanbul, reported in the writings of traveler Evliya Çelebi to have achieved sustained unpowered flight.
## Etymology of name {#etymology_of_name}
The title *\"Hezârfen\"*, given by Evliyâ Çelebi to Ahmed Çelebi, is from Persian هزار *hezār* meaning -a thousand- + فنّ *fann* meaning -science together making it together Ahmed having talents in \"a thousand of sciences (polymath).
## Non-powered flight {#non_powered_flight}
The 17th century writings of Evliyâ Çelebi relate this story of Hezârfen Ahmed Çelebi, circa 1630--1632:
## Legacy
- One of 4 airports in Istanbul is named the \"Hezarfen Airfield\".
- A 1996 feature-length film, \"Istanbul Beneath My Wings\" (*İstanbul Kanatlarımın Altında*) concerns the lives of Hezârfen Ahmet Çelebi, his brother and purported rocket aviator Lagari Hasan Çelebi (per the same single source, Çelebi, as the above story), and Ottoman society in the early 17th century, as witnessed and narrated by Evliya Çelebi.
- The Turkish children's TV show "Little Hezarfen" (*Küçük Hezarfen*) is about Hezârfen Ahmet Çelebi\'s childhood, though the events that occur within the show are likely fictitious and/or exaggerated. A main theme within the show, however, is Hezarfen\'s desire to build wings that allow him to fly
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# Hans Gerhard Creutzfeldt
**Hans Gerhard Creutzfeldt** (June 2, 1885 -- December 30, 1964) was a German neurologist and neuropathologist. Although he is typically credited as the physician to first describe the Creutzfeldt--Jakob disease, this has been disputed. He was born in Harburg an der Elbe and died in Munich.
## Biography
Creutzfeldt was born into a medical family, on June 2, 1885, at Harburg an der Elbe, Germany, which was incorporated into Hamburg in 1937. In 1903, at the age of 18, he was drafted into the German army and spent his service stationed in Kiel.
Afterwards, he attended the School of Medicine of the University of Jena and the University of Rostock, receiving his doctorate at the latter in 1909. Part of his practical training was undertaken at *St. Georg* -- Hospital in Hamburg. After qualification he sought adventure as a ship\'s surgeon, voyaging the Pacific Ocean, taking the opportunity to study local crafts, linguistics, and tropical plants.
After returning to Germany in 1912, Creutzfeldt worked at the Neurological Institute in Frankfurt am Main, at the psychiatric-neurological clinics in Breslau, Kiel and Berlin, and at the *Deutsche Forschungsanstalt für Psychiatrie* in Munich.
During the First World War, Creutzfeldt was deployed as a reserve medical officer and survived the sinking of the auxiliary cruiser SMS Greif, on which he was embarked. After being captured on February 29, 1916, he was repatriated as a doctor in May of that year and served in the Imperial German Navy until the end of the war in 1918.
Creutzfeldt was habilitated at Kiel in 1920, and in 1925 became *Extraordinarius* of psychiatry and neurology. In 1938 he was appointed professor and director of the university psychiatric and neurological division in Kiel. He helped to recognize a neurodegenerative disease, with Alfons Maria Jakob, Creutzfeldt--Jakob disease in which the brain tissue develops holes and takes on a sponge-like texture. It is now known it is due to a type of infectious protein called a prion. Prions are misfolded proteins which replicate by converting their properly folded counterparts.
In Nazi Germany, Creutzfeldt became a Patron Member of Heinrich Himmler\'s SS from 1932 to 1933.
## Later life {#later_life}
Creutzfeldt was 54 years old when the Second World War broke out. He was unmoved by the Nazi regime and was able to save some people from death in concentration camps and also managed to save almost all of his patients from being murdered under the Nazi *Aktion T4* involuntary euthanasia program, while most mental patients identified by T4 personnel were gassed or poisoned at separate euthanasia clinics such as Hadamar Euthanasia Centre. During the war, bombing raids destroyed his home and clinic.
After the war he was director of the University of Kiel for six months, before being dismissed by the British occupation forces. His efforts to rebuild the university caused a series of conflicts with the British because he wanted to allow more former army officers to study there. Creutzfeldt resigned from his work at Kiel in 1953 in order to pursue life as professor emeritus in Munich.
## Personal life {#personal_life}
He was married to Clara Sombart, a daughter of economist Werner Sombart. They had five children, among them neurologist Otto Detlev Creutzfeldt and Werner Creutzfeldt (1924--2006), a German internist. He died in December 1964 in Munich
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# Harbor
A **harbor** (American English), or **harbour** (Commonwealth English; see spelling differences), is a sheltered body of water where ships, boats, and barges can be moored. The term *harbor* is often used interchangeably with *port*, which is a man-made facility built for loading and unloading vessels and dropping off and picking up passengers. Harbors usually include one or more ports. Alexandria Port in Egypt, meanwhile, is an example of a port with two harbors.
Harbors may be natural or artificial. An artificial harbor can have deliberately constructed breakwaters, sea walls, or jetties or they can be constructed by dredging, which requires maintenance by further periodic dredging. An example of an artificial harbor is Long Beach Harbor, California, United States, which was an array of salt marshes and tidal flats too shallow for modern merchant ships before it was first dredged in the early 20th century. In contrast, a natural harbor is surrounded on several sides by land. Examples of natural harbors include Sydney Harbour, New South Wales, Australia, Halifax Harbour in Halifax, Nova Scotia, Canada and Trincomalee Harbour in Sri Lanka.
## Artificial harbors `{{anchor|Artificial harbor|Artificial harbour|Artificial harbours}}`{=mediawiki} {#artificial_harbors}
Artificial harbors are frequently built for use as ports. The oldest artificial harbor known is the Ancient Egyptian site at Wadi al-Jarf, on the Red Sea coast, which is at least 4500 years old (ca. 2600--2550 BCE, reign of King Khufu). The largest artificially created harbor is Jebel Ali in Dubai. Other large and busy artificial harbors include:
- Port of Long Beach and Los Angeles, California, United States
- Port of Casablanca, Morocco
- Port of Koper, Slovenia
The Ancient Carthaginians constructed fortified, artificial harbors called cothons.
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# Harbor
## Natural harbors `{{anchor|Natural harbor|Natural harbour|Natural harbours}}`{=mediawiki} {#natural_harbors}
A natural harbor is a landform where a section of a body of water is protected and deep enough to allow anchorage. Many such harbors are rias. Natural harbors have long been of great strategic naval and economic importance, and many great cities of the world are located on them. Having a protected harbor reduces or eliminates the need for breakwaters as it will result in calmer waves inside the harbor. Some examples are: `{{div col|colwidth=23em}}`{=mediawiki}
- Bali Strait, Indonesia
- Berehaven Harbour, Ireland
- Balikpapan Bay in East Kalimantan, Indonesia
- Mumbai in Maharashtra, India
- Boston Harbor in Massachusetts, United States
- Burrard Inlet in Vancouver, British Columbia, Canada
- Chittagong in Chittagong Division, Bangladesh
- Cork Harbour, Ireland
- Esquimalt Harbour in Esquimalt, British Columbia, Canada
- Grand Harbour, Malta
- Guantánamo Bay, Cuba
- Gulf of Paria, Trinidad and Tobago
- Haifa Bay, in Haifa, Israel
- Halifax Harbour in Nova Scotia, Canada
- Hamilton Harbour in Ontario, Canada
- Killybegs in County Donegal, Ireland
- Kingston Harbour, Jamaica
- Mahón harbour, in Menorca, Spain
- Marsamxett Harbour, Malta
- Milford Haven in Wales, United Kingdom
- New York Harbor in the United States
- Pago Pago Harbor in American Samoa
- Pearl Harbor in Hawaii, United States
- Poole Harbour in England, United Kingdom
- Port Hercules, Monaco
- Sydney Harbour in New South Wales, Australia, technically a ria
- Port Stephens in Australia
- Tanjung Perak in Surabaya, Indonesia
- Port of Tobruk in Tobruk, Libya
- Presque Isle Bay in Pennsylvania, United States
- Prince William Sound in Alaska, United States
- Puget Sound in Washington state, United States
- Rías Altas and Rías Baixas in Galicia, Spain
- Roadstead of Brest in Brittany, France
- San Diego Bay in California, United States
- San Francisco Bay in California, United States
- Scapa Flow in Scotland, United Kingdom
- Sept-Îles in Côte-Nord, Quebec, Canada
- Shelburne in Nova Scotia, Canada
- Subic Bay in Zambales, Philippines
- Tallinn Bay in Tallinn, Estonia
- Tampa Bay in Florida, United States
- Trincomalee Harbour, Sri Lanka
- Tuticorin in Tamil Nadu, India
- Victoria Harbour in Hong Kong, China
- Visakhapatnam Harbour, India
- Vizhinjam in Trivandrum, India
- Waitematā Harbour in Auckland, New Zealand
- Manukau Harbour in Auckland, New Zealand
- Wellington Harbour in Wellington, New Zealand
- Port Foster in Deception Island, Antarctica
## Ice-free harbors `{{anchor|Ice-free harbor|Ice-free harbour|Ice-free harbours}}`{=mediawiki} {#ice_free_harbors}
For harbors near the North and South poles, being ice-free is an important advantage, especially when it is year-round. Examples of these are:
- Hammerfest, Norway
- Liinakhamari, Russia
- Murmansk, Russia
- Nakhodka in Nakhodka Bay, Russia
- Pechenga, Russia
- Prince Rupert, Canada
- Valdez, United States
- Vardø, Norway
- Vostochny Port, Russia
The world\'s southernmost harbor, located at Antarctica\'s Winter Quarters Bay (77° 50′ South), is sometimes ice-free, depending on the summertime pack ice conditions.
## Important harbors `{{anchor|Important harbor|Important harbour|Important harbours}}`{=mediawiki} {#important_harbors}
`{{Excessive examples|date=June 2025|section}}`{=mediawiki} Although the world\'s busiest port is a contested title, in 2017 the world\'s busiest harbor by cargo tonnage was the Port of Ningbo-Zhoushan.
The following are large natural harbors:
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# Horseshoe
A **horseshoe** is a product designed to protect a horse hoof from wear. Shoes are attached on the palmar surface (ground side) of the hooves, usually nailed through the insensitive hoof wall that is anatomically akin to the human toenail, although much larger and thicker. However, there are also cases where shoes are glued.
Horseshoes are available in a wide variety of materials and styles, developed for different types of horses and for the work they do. The most common materials are steel and aluminium, but specialized shoes may include use of rubber, plastic, magnesium, titanium, or copper. Steel tends to be preferred in sports in which a strong, long-wearing shoe is needed, such as polo, eventing, show jumping, and western riding events. Aluminium shoes are lighter, making them common in horse racing where a lighter shoe is desired, and often facilitate certain types of movement; they are often favored in the discipline of dressage. Some horseshoes have \"caulkins\", \"caulks\", or \"calks\": protrusions at the toe or heels of the shoe, or both, to provide additional traction.
The fitting of horseshoes is a professional occupation, conducted by a farrier, who specializes in the preparation of feet, assessing potential lameness issues, and fitting appropriate shoes, including remedial features where required. In some countries, such as the UK, horseshoeing is legally restricted to people with specific qualifications and experience. In others, such as the United States, where professional licensing is not legally required, professional organizations provide certification programs that publicly identify qualified individuals.
When kept as a talisman, a horseshoe is said to bring good luck. A stylized variation of the horseshoe is used for a popular throwing game, horseshoes.
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# Horseshoe
## History
Since the early history of domestication of the horse, working animals were found to be exposed to many conditions that created breakage or excessive hoof wear. Ancient people recognized the need for the walls (and sometimes the sole) of domestic horses\' hooves to have additional protection over and above any natural hardness. An early form of hoof protection was seen in ancient Asia, where horses\' hooves were wrapped in rawhide, leather, or other materials for both therapeutic purposes and protection from wear. From archaeological finds in Great Britain, the Romans appeared to have attempted to protect their horses\' feet with a strap-on, solid-bottomed \"hipposandal\" that has a slight resemblance to the modern hoof boot.
Historians differ on the origin of the horseshoe. Because iron was a valuable commodity, and any worn out items were generally reforged and reused, it is difficult to locate clear archaeological evidence. Although some credit the Druids, there is no hard evidence to support this claim. In 1897 four bronze horseshoes with what are apparently nail holes were found in an Etruscan tomb dated around 400 BC. The assertion by some historians that the Romans invented the \"mule shoes\" sometime after 100 BC is supported by a reference by Catullus who died in 54 BC. However, these references to use of horseshoes and muleshoes in Rome may have been to the \"hipposandal\"---leather boots, reinforced by an iron plate, rather than to nailed horseshoes.
Existing references to the nailed shoe are relatively late, first known to have appeared around AD 900, but there may have been earlier uses given that some have been found in layers of dirt. There are no extant references to nailed horseshoes prior to the reign of Byzantine Emperor Leo VI, and by 973 occasional references to them can be found. The earliest clear written record of iron horseshoes is a reference to \"crescent figured irons and their nails\" in AD 910. There is very little evidence of any sort that suggests the existence of nailed-on shoes prior to AD 500 or 600, though there is a find dated to the fifth century AD of a horseshoe, complete with nails, found in the tomb of the Frankish King Childeric I at Tournai, Belgium.
Around 1000 AD, cast bronze horseshoes with nail holes became common in Europe. A design with a scalloped outer rim and six nail holes was common. According to Gordon Ward the scalloped edges were created by double punching the nail holes causing the edges to bulge. The 13th and 14th centuries brought the widespread manufacturing of iron horseshoes. By the time of the Crusades (1096--1270), horseshoes were widespread and frequently mentioned in various written sources. In that period, due to the value of iron, horseshoes were even accepted in lieu of coin to pay taxes.
By the 13th century, shoes were forged in large quantities and could be bought ready made. Hot shoeing, the process of shaping a heated horseshoe immediately before placing it on the horse, became common in the 16th century. From the need for horseshoes, the craft of blacksmithing became \"one of the great staple crafts of medieval and modern times and contributed to the development of metallurgy.\" A treatise titled \"No Foot, No Horse\" was published in England in 1751.
In 1835, the first U.S. patent for a horseshoe manufacturing machine capable of making up to 60 horseshoes per hour was issued to Henry Burden. In mid-19th-century Canada, marsh horseshoes kept horses from sinking into the soft intertidal mud during dike-building. In a common design, a metal horseshoe holds a flat wooden shoe in place.
### China
In China, iron horseshoes became common during the Yuan dynasty (1271--1368), prior to which rattan and leather shoes were used to preserve animal hooves. Evidence of the preservation of horse hooves in China dates to the Warring States period (476--221 BC), during which Zhuangzi recommended shaving horse hooves to keep them in good shape. The Discourses on Salt and Iron in 81 BC mentions using leather shoes, but it is not clear if they were used for protecting horse hooves or to aid in mounting the horse. Remnants of iron horseshoes have been found in what is now northeast China, but the tombs date to the Goguryeo period in 414 AD. A mural in the Mogao Caves dated to 584 AD depicts a man caring for a horse\'s hoof, which some speculate might be depicting horseshoe nailing, but the mural is too eroded to tell clearly.
The earliest reference to iron horseshoes in China dates to 938 AD during the Five Dynasties and Ten Kingdoms period. A monk named Gao Juhui sent to the Western Regions writes that the people in Ganzhou (now Zhangye) taught him how to make \"horse hoof *muse*\", which had four holes in it that connected to four holes in the horse\'s hoof, and were thus put together. They also recommended using yak skin shoes for camel hooves. Iron horseshoes however did not become common for another three centuries. Zhao Rukuo writes in *Zhu Fan Zhi*, finished in 1225, that the horses of the Arabs and Persians used metal for horse shoes, implying that horses in China did not. After the establishment of the Yuan dynasty in 1271 AD, iron horseshoes became more common in northern China. When Thomas Blakiston travelled up the Yangtze, he noted that in Sichuan \"cattle wore straw shoes to prevent their slipping on the wet ground\" while in northern China, \"horses and cattle are shod with iron shoes and nails.\" The majority of Chinese horseshoe discoveries have been in Jilin, Heilongjiang, Liaoning, Sichuan, and Tibet.
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# Horseshoe
## Reasons for use {#reasons_for_use}
### Environmental changes linked to domestication {#environmental_changes_linked_to_domestication}
Many changes brought about by the domestication of the horse, such as putting them in wetter climates and exercising them less, have led to horses\' hooves hardening less and being more vulnerable to injury. In the wild, a horse may travel up to 50 mi per day to obtain adequate forage. While horses in the wild cover large areas of terrain, they usually do so at relatively slow speeds, unless being chased by a predator. They also tend to live in arid steppe climates. The consequence of slow but nonstop travel in a dry climate is that horses\' feet are naturally worn to a small, smooth, even, and hard state. The continual stimulation of the sole of the foot keeps it thick and hard. However, in domestication, the manner in which horses are used is different. Domesticated horses are brought to colder and wetter areas than their ancestral habitat. These softer and heavier soils soften the hooves and make them prone to splitting, thus making hoof protection necessary.
### Physical stresses requiring horseshoes {#physical_stresses_requiring_horseshoes}
- Abnormal stress: Horses\' hooves can become quite worn out when subjected to the added weight and stress of a rider, pack load, cart, or wagon.
- Corrective shoeing: The shape, weight, and thickness of a horseshoe can significantly affect the horse\'s gait. Farriers may forge custom shoes to help horses with bone or muscle problems in their legs, or fit commercially available remedial shoes.
- Traction: Traction devices such as borium for ice, horse shoe studs for muddy or slick conditions, calks, carbide-tipped road nails and rims are useful for performance horses such as eventers, show jumpers, polo ponies, and other horses that perform at high speeds, over changing terrain, or in less-than-ideal footing.
- Gait manipulation: Some breeds such as the Saddlebred, Tennessee Walking Horse, and other gaited horses are judged on their high-stepping movement. Special shoeing can help enhance their natural movement.
- Racing horses with weakness in their foot or leg require specialized horseshoes.
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# Horseshoe
## Horseshoeing theories and debates {#horseshoeing_theories_and_debates}
Domestic horses do not always require shoes. When possible, a \"barefoot\" hoof, at least for part of every year, is a healthy option for most horses. However, horseshoes have their place and can help prevent excess or abnormal hoof wear and injury to the foot. Many horses go without shoes year round, some using temporary protection such as hoof boots for short-term use.
## Process of shoeing {#process_of_shoeing}
Shoeing, when performed correctly, causes no pain to the animal. Farriers trim the insensitive part of the hoof, which is the same area into which they drive the nails. This is analogous to a manicure on a human fingernail, only on a much larger scale.
Before beginning to shoe, the farrier removes the old shoe using pincers (shoe pullers) and trims the hoof wall to the desired length with nippers, a sharp pliers-like tool, and the sole and frog of the hoof with a hoof knife. Shoes do not allow the hoof to wear down as it naturally would in the wild, and it can then become too long. The coffin bone inside the hoof should line up straight with both bones in the pastern. If the excess hoof is not trimmed, the bones will become misaligned, which would place stress on the legs of the animal.
Shoes are then measured to the foot and bent to the correct shape using a hammer, anvil, forge, and other modifications, such as taps for shoe studs, are added. Farriers may either cold shoe, in which they bend the metal shoe without heating it, or hot shoe, in which they place the metal in a forge before bending it. Hot shoeing can be more time-consuming, and requires the farrier to have access to a forge; however, it usually provides a better fit, as the mark made on the hoof from the hot shoe can show how even it lies. It also allows the farrier to make more modifications to the shoe, such as drawing toe- and quarter-clips. The farrier must take care not to hold the hot shoe against the hoof too long, as the heat can damage the hoof.
Hot shoes are placed in water to cool them. The farrier then nails the shoes on by driving the nails into the hoof wall at the white line of the hoof. The nails are shaped in such a way that they bend outward as they are driven in, avoiding the sensitive inner part of the foot, so they emerge on the sides of the hoof. When the nail has been completely driven, the farrier cuts off the sharp points and uses a clincher (a form of tongs made especially for this purpose) or a clinching block with hammer to bend the rest of the nail so it is almost flush with the hoof wall. This prevents the nail from getting caught on anything, and also helps to hold the nail, and therefore the shoe, in place.
The farrier then uses a rasp (large file), to smooth the edge where it meets the shoe and eliminate any sharp edges left from cutting off the nails.
Hot Horseshoe (stevefe).jpg\|A hot horseshoe in a forge Farrier toolslabled.JPG\|Farrier tools Italian farrier 2006 2.jpg\|Nailing on the shoe Shoeing in progress.jpg\|The nails driven through the hoof, but not yet bent downwards
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# Horseshoe
## In culture {#in_culture}
### Superstition
Horseshoes have long been considered lucky. They were originally made of iron, a material that was believed to ward off evil spirits, and traditionally were held in place with seven nails, seven being the luckiest number.
The tradition of using worn horseshoes as protective charms dates back to Europe, where they were often placed above or beside doorways. This practice aimed to guard homes, barns, and stables, and remnants of this custom can still be seen across regions like Italy, Germany, Britain, and Scandinavia. Horseshoe-shaped wall decorations are also common. In the Middle East, blue-glazed terra cotta horseshoe plaques are widely used, while in Turkey, metal or blue glass horseshoes are combined with the \"all-seeing eye\" to create distinctive protective talismans believed to ward off the evil eye.
Opinion is divided as to which way up the horseshoe ought to be nailed. In much of Europe, the Middle East, and Latin America, it is typically hung facing downward, symbolising the pouring of blessings or protection as it allows good fortune to flow onto those passing beneath. However, in parts of Ireland and Britain, an upward orientation is preferred, based on the belief that it catches luck and prevents it from \"running out.\" These differing traditions were carried to the United States, where those of English and Irish heritage often hang horseshoes upward, while French, German, Italian, Spanish, and Balkan influences favor a downward position.
Despite these differences in interpretation, the horseshoe's true primary purpose is to serve as a protective charm, regardless of its orientation, rather than merely a luck-catching device.
The superstition acquired a further Christian twist due to a legend surrounding the tenth-century saint Dunstan, who worked as a blacksmith before becoming Archbishop of Canterbury. The legend recounts that, one day, the Devil walked into Dunstan\'s shop and asked him to shoe his horse. Dunstan pretended not to recognize him, and agreed to the request; but rather than nailing the shoe to the horse\'s hoof, he nailed it to the Devil\'s own foot, causing him great pain. Dunstan eventually agreed to remove the shoe, but only after extracting a promise that the Devil would never enter a household with a horseshoe nailed to the door.
In the tale of Saint Dunstan, it appears that hanging a horseshoe with the open end facing downward is the most accurate interpretation. This is suggested by a passage from the story:
"He will not through Granāda march, For there he knows the horse-shoe arch
At every gate attends him.
Nor partridges can he digest,
Since the dire horse-shoe on the breast,
Most grievously offends him."
The mention of the \"horse-shoe arch\" likely refers to a horseshoe with its open ends facing downward, consistent with the illustrations found throughout the tale.
Blacksmiths and Horseshoes also have a connection. Blacksmiths themselves were historically considered lucky and revered for their craft, as they worked with fire and iron, both seen as powerful and protective elements. Their association with luck extended to the horseshoes they forged, which became symbols of protection and good fortune. Blacksmiths often hung horseshoes with the ends pointing down, believing this orientation would allow blessings and luck to pour onto their work.
### Heraldry
In heraldry, horseshoes most often occur as canting charges, such as in the arms of families with names like Farrier, Marshall, and Smith. A horseshoe (together with two hammers) also appears in the arms of Hammersmith and Fulham, a borough in London.
The flag of Rutland, England\'s smallest historic county, consists of a golden horseshoe laid over a field scattered with acorns. This refers to an ancient tradition in which every noble visiting Oakham, Rutland\'s county town, presents a horseshoe to the Lord of the Manor, which is then nailed to the wall of Oakham Castle. Over the centuries, the Castle has amassed a vast collection of horseshoes, the oldest of which date from the 15th century.
### Monuments and structures {#monuments_and_structures}
A massive golden horseshoe structure is erected over the shopping mall of the Tuuri village in Alavus, a town of Finland. It is one of the most famous monuments in the locality; however, it stands at number three in Reuters\' list of world\'s ugliest buildings and monuments.
### Sport
The sport of horseshoes involves a horseshoe being thrown as close as possible to a rod in order to score points. As far as it is known, the sport is as old as horseshoes themselves. While traditional horseshoes can still be used, most organized versions of the game use specialized sport horseshoes, which do not fit on horses\' hooves
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# Marrubium vulgare
***Marrubium vulgare*** (**white horehound** or **common horehound**) is a flowering plant in the mint family (Lamiaceae), native to Europe, northern Africa, and southwestern and central Asia. Specifically, it emerged in the region between the Mediterranean Sea and Central Asia and now inhabits all continents. It is also widely naturalized in many places, including most of North and South America.
It is a grey-leaved herbaceous perennial plant, and grows to 25 - tall. The leaves are 2 - long with a densely crinkled surface, and are covered in downy hairs. The flowers are white, borne in clusters on the upper part of the main stem.
## Etymology
The Oxford English Dictionary derives the word *horehound* from Old English *hoar* (furry, as in \"hoarfrost\") and *hune* (a word of unknown origin designating a class of herbs or plants). The second element was altered by folk etymology. The word \"White\" is generally used in botanical contexts, to distinguish it from Black Horehound, *Ballota nigra*, a similar-looking herb.
## Uses
### Folk medicine {#folk_medicine}
thumb\|upright=.8\|Celsus\' *De medicina* in the Aldine edition of 1528 White horehound has been mentioned in conjunction with use as a folk medicine dating at least back to the 1st century BC, where it appeared as a remedy for respiratory ailments in the treatise *De Medicina* by Roman encyclopaedist Aulus Cornelius Celsus. The Roman agricultural writer Columella lists it as a remedy for expelling worms in farm animals in his important first-century work *On Agriculture*. Since then, white horehound has appeared for similar purposes in numerous herbals over the centuries, such as *The Herball, or, Generall historie of plantes* by John Gerard, and *Every Man His Own Doctor: or, The Poor Planter's Physician*.
*M. vulgare* has been described in monographs of the German Commission E as a treatment for colds, as a digestive, and as a choleretic. It is one of the ingredients of the Ricola throat lozenge. The U.S. Food and Drug Administration does not endorse the plant for use as a drug, but includes it as a safe food additive.
### Culinary
thumb\|upright=.8\|A container of horehound candies from Fuzziwig\'s Candy Factory
Horehound candy drops are bittersweet hard candies like cough drops made with sugar and an extract of *M. vulgare*. They are dark-colored, dissolve in the mouth, and have a flavor that has been compared to menthol and root beer. Like other products derived from *M. vulgare*, they are sometimes used as an unproven folk treatment for coughs and other ailments.
*M. vulgare* is used to make beverages such as horehound beer (similar to root beer), horehound herbal tea (similar to the Maghrebi mint tea), and the rock and rye cocktail.
## As an invasive weed {#as_an_invasive_weed}
Horehound was introduced to southern Australia in the 19th century as a medicinal herb. It became a weed of native grasslands and pastures where it was introduced with settlers\' livestock and was first declared under noxious weeds legislation. It now appears to have reached its full potential distribution.
In New Zealand, efforts are being made to control its spread with biocontrol measures using the horehound clearwing moth (*Chamaesphecia mysiniformis*) and the horehound plume moth (*Wheeleria spilodactylus*), which can eat their way through many plants.
Horehound is usually found in disturbed and overgrazed areas. It is highly unpalatable to livestock, so livestock eat other plants around it, a process that favors the persistence and spread of the weed. It may persist in native vegetation that has been grazed.
## As biocontrol {#as_biocontrol}
*Marrubium vulgare* is also used as a natural grasshopper repellent in agriculture.
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# Marrubium vulgare
## In astrology {#in_astrology}
According to 14th century English poet John Gower, in Book 7 of *his Confessio Amantis*, this plant was the herb of the fourth star of `{{Clarify span|Nectanebus' astrology|date=December 2021}}`{=mediawiki}, Capella. Gower uses the older name, Alhaiot (VII:1338).
## Gallery
<File:Marrubium> vulgare.JPG\|Wild horehound <File:Marrubium> vulgare0.jpg\|Flowers <File:Marrubium> vulgare.jpg\|Foliage of young plants <File:Horehound> bug.jpg\|Horehound bug (*Agonoscelis rutila*), an insect that feeds on the plant <File:Marrubium> vulgare in Mexico II
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# Source tracking
**Source tracking** pertains to the ability of some hypertext systems to rigorously track the exact source of every document or partial document included in the system; that is, they remember who entered the information, when it was entered, when it was updated and by whom, and so on. This allows determining the exact history of every document (and even small parts of documents).
Present HTML and HTTP do not have this feature, but certain systems on the World Wide Web (such as WikiWiki and Everything Engine) may have limited versions of the capability.
One application of digital watermarking is source tracking
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# Hans Selye
**János Hugo Bruno** \"**Hans**\" **Selye** `{{post-nominals|country= CAN|CC}}`{=mediawiki} (`{{IPAc-en|ˈ|s|ɛ|l|j|eɪ}}`{=mediawiki}`{{Dubious|date=November 2021}}`{=mediawiki}; *Selye János* `{{IPA|hu|ˈʃɛjɛ}}`{=mediawiki}; January 26, 1907 -- October 16, 1982) was a Hungarian-Canadian endocrinologist who conducted important scientific work on the hypothetical non-specific response of an organism to stressors. Although he did not recognize all of the many aspects of glucocorticoids, Selye was aware of their role in the stress response.
## Biography
Selye was born in Vienna, Austria-Hungary on January 26, 1907, and grew up in Komárom (the town with Hungarian majority in present-day Slovakia was cut by the Treaty of Trianon in 1920). Selye\'s father was a doctor of Hungarian ethnicity and his mother was Austrian. He became a Doctor of Medicine and Chemistry in Prague in 1929 and went on to do pioneering work in stress and endocrinology at Johns Hopkins University, McGill University, and the Université de Montréal. He was nominated for the Nobel Prize in Physiology or Medicine for the first time in 1949. Although he received a total of 17 nominations (1949--1953) in his career, he never won the prize.
Selye died on October 16, 1982, in Montreal, Quebec, Canada. He often returned to visit Hungary, giving lectures as well as interviews in Hungarian television programs. He conducted a lecture in 1973 at the Hungarian Scientific Academy in Hungarian and observers noted that he had no accent, despite spending many years abroad. His book *The Stress of Life* appeared in Hungarian as *Az Életünk és a stressz* in 1964 and became a bestseller. Selye János University, the only Hungarian-language university in Slovakia, was named after him. Selye\'s mother was killed by gunfire during Hungary\'s anti-Communist revolt of 1956.
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# Hans Selye
## Stress research {#stress_research}
Selye\'s interest in stress began when he was in medical school; he had observed that patients with various chronic illnesses like tuberculosis and cancer appeared to display a common set of symptoms that he attributed to what is now commonly called stress. After completing his medical degree and a doctorate degree in organic chemistry at the German University of Prague, he received a Rockefeller Foundation fellowship to study (1931) at Johns Hopkins in Baltimore and later moved to the Department of Biochemistry at McGill University in Montreal in 1932 where he studied under the sponsorship of James Bertram Collip (1892--1965). While working with laboratory animals, Selye observed a phenomenon that he thought resembled what he had previously seen in chronic patients. Rats exposed to cold, drugs, or surgical injury exhibited a common pattern of responses to these stressors. (A stressor is a chemical or biological agent, environmental condition, external stimulus or an event seen as causing stress to an organism.)
Selye initially (c. 1940s) called this the \"general adaptation syndrome\" (at the time it was also called \"Selye\'s syndrome\"), but he later rebaptized it with the simpler term \"stress response\". According to Selye the general adaptation syndrome is triphasic, involving an initial **alarm phase** followed by a stage of **resistance or adaptation** and, finally, a stage of **exhaustion** and death (these phases were established largely on the basis of glandular states). Working with doctoral student Thomas McKeown (1912--1988), Selye published a report that used the word \"stress\" to describe these responses to adverse events.`{{request quotation|date=May 2023}}`{=mediawiki}
His last inspiration for general adaptation syndrome came from an experiment in which he injected mice with extracts of various organs. He at first believed that he had discovered a new hormone, but was proved wrong when every irritating substance he injected produced the same symptoms (swelling of the adrenal cortex, atrophy of the thymus, gastric and duodenal ulcers). This, paired with his observation that people with different diseases exhibit similar symptoms, led to his description of the effects of \"noxious agents\" as he at first called it. He later adopted the term \"stress\", which has been accepted into the lexicon of many languages.
Selye argued that stress differs from other physical responses in that it is identical whether the provoking impulse is positive or negative. He called negative stress \"distress\" and positive stress \"eustress\".
The system whereby the body copes with stress, the hypothalamic-pituitary-adrenal axis (HPA axis) system, was also first described by Selye.
Selye acknowledged the influence of Claude Bernard (1813--1878), who developed the idea of *milieu intérieur*, and of the \"homeostasis\" of Walter Cannon (1871--1945). Selye conceptualized the physiology of stress as having two components: a set of responses which he called the \"general adaptation syndrome\", and the development of a pathological state from ongoing, unrelieved stress.
While Selye\'s work attracted continued support from advocates of psychosomatic medicine, many in experimental physiology concluded that his concepts were too vague and unmeasurable. During the 1950s, Selye turned away from the laboratory to promote his concept through popular books and lecture tours. He wrote both for non-academic physicians and an international bestseller entitled *The Stress of Life* (1956). From the late 1960s, academic psychologists started to adopt Selye\'s concept of stress, and he followed *The Stress of Life* with two other books for the general public, *From Dream to Discovery: On Being a Scientist* (1964) and *Stress without Distress* (1974). The idea of \"stress\" resonated with humanistic psychology, and pop psychology generalised the concept.
Selye worked as a professor and director of the Institute of Experimental Medicine and Surgery at the Université de Montréal. In 1975 he founded the International Institute of Stress, and in 1979, Selye and Arthur Antille started the Hans Selye Foundation. Later Selye and eight Nobel laureates founded the Canadian Institute of Stress.
In 1968 he was made a Companion of the Order of Canada. In 1976 Concordia University awarded him the Loyola Medal. In 1976, he received the American Academy of Achievement\'s Golden Plate Award at a Banquet of the Golden Plate ceremony in San Diego, California.
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# Hans Selye
## Controversy and involvement with the tobacco industry {#controversy_and_involvement_with_the_tobacco_industry}
Although it was not widely known at the time, Selye began consulting for the tobacco industry starting in 1958; he had previously sought funding from the industry, but had been denied. Later, New York attorney Edwin Jacob contacted Selye as he prepared a defense against liability actions brought against tobacco companies. The companies wanted Selye\'s help in arguing that the recognized correlation between smoking and cancer was not proof of causality. The firm offered to pay Selye \$1000 to make a statement supporting this claim. He agreed but refused to testify. Tobacco industry lawyers reported that Selye was willing to incorporate industry advice when writing about smoking and stress. One lawyer advised him to \"comment on the unlikelihood of there being a mechanism by which smoking could cause cardiovascular disease" and to emphasize the \"stressful\" effect that anti-smoking messages had on the US population.
Publicly, Selye never declared his consultancy work for the tobacco industry. In a 1967 letter to \"Medical Opinion and Review\", he argued against government over-regulation of science and public health, implying that his views on smoking were objective: \"I purposely avoided any mention of government-supported research because, being too largely dependent upon it, I may not be able to view the subject objectively. However, I do not use ... cigarettes so let these examples suffice.\" In June 1969, Selye (then director of the Institute of Experimental Pathology, University of Montreal) testified before the Canadian House of Commons Health Committee against anti-smoking legislation, opposing advertising restrictions, health warnings, and restrictions on tar and nicotine. For his testimony Selye was funded \$50,000 per year for a 3-year \"special project\", by William Thomas Hoyt, executive of Council for Tobacco Research, with another \$50,000 a year pledged by the Canadian tobacco industry. His comments on smoking were used worldwide; Philip Morris used Selye\'s statements on the benefits of smoking to argue against the use of health warnings on tobacco products in Sweden. Similarly, in 1977 the Australian Cigarette Manufacturers quoted Selye extensively in their submission to the Australian Senate Standing Committee on Social Welfare.
In 1999, the United States Department of Justice brought an anti-racketeering case against 7 tobacco companies --British American Tobacco, Brown & Williamson, Philip Morris, Liggett, American Tobacco Company, RJ Reynolds, and Lorillard-- plus the Council for Tobacco Research, and the Tobacco Institute. As a result, the industry\'s influence on stress research was revealed.
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# Hans Selye
## Former graduate students {#former_graduate_students}
- Roger Guillemin
- Paola S. Timiras
## Publications
- [\"A Syndrome Produced by Diverse Nocuous Agents\"](https://web.archive.org/web/20080107091947/http://neuro.psychiatryonline.org/cgi/content/full/10/2/230a) - 1936 article by Hans Selye from [The journal of neuropsychiatry and clinical neurosciences](http://neuro.psychiatryonline.org/)
- *The Stress of Life*. New York: McGraw-Hill, 1956, `{{ISBN|978-0070562127}}`{=mediawiki}
-
- *From Dream to Discovery: On being a scientist*. New York: McGraw-Hill 1964, `{{ISBN|978-0405066160}}`{=mediawiki}
- *Hormones and Resistance*. Berlin; New York: Springer-Verlag, 1971, `{{ISBN|978-3540054115}}`{=mediawiki}
- *Stress Without Distress*. Philadelphia: J. B. Lippincott Co
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# Help desk
`{{E-commerce}}`{=mediawiki} A **help desk** is a department or person that provides assistance and information, usually for electronic or computer problems. In the mid-1990s, research by Iain Middleton of Robert Gordon University studied the value of an organization\'s help desks. It found that value was derived not only from a reactive response to user issues, but also from the help desk\'s unique position of communicating daily with numerous customers or employees. Information gained in areas such as technical problems, user preferences, and satisfaction can be valuable for the planning and development work of other information technology units.
A main function of the help desk is to separate issues from defects. Many issues can be solved at the help desk level such as password resets and simple misunderstandings. Some issues will be the result of actual product defect which should be forwarded to a development team for resolution.
Large help desks have a person or team responsible for managing the incoming requests, called \"issues\"; they are commonly called queue managers or queue supervisors. The queue manager is responsible for the issue queues, which can be set up in various ways depending on the help desk size or structure. Typically, large help desks have several teams that are experienced in working on different issues. The queue manager will assign an issue to one of the specialized teams based on the type of issue raised. Some help desks may have telephone systems with ACD splits ensuring that calls about specific topics are put through to analysts with the requisite experience or knowledge
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# Hannes Bok
**Wayne Francis Woodard** (`{{IPAc-en|ˈ|w|ʊ|d|ər|d}}`{=mediawiki} `{{respell|WUUD|ərd}}`{=mediawiki}; July 2, 1914 -- April 11, 1964), known by the pseudonym **Hannes Bok**,`{{pronunciation needed|date=September 2024}}`{=mediawiki} was an American artist and illustrator, as well as an amateur astrologer and writer of fantasy fiction and poetry. He painted nearly 150 covers for various science fiction, fantasy, and detective fiction magazines, as well as contributing hundreds of black and white interior illustrations. Bok\'s work graced the pages of calendars and early fanzines, as well as dust jackets from specialty book publishers like Arkham House, Llewellyn, Shasta Publishers, and Fantasy Press. His paintings achieved a luminous quality through the use of an arduous glazing process, which was learned from his mentor, Maxfield Parrish. Bok shared one of the inaugural 1953 Hugo Awards for science fiction achievement (best Cover Artist).
## Life and career {#life_and_career}
Wayne Woodard (the name is sometimes mistakenly rendered as \"Woodward\") was born in Kansas City, Missouri. His parents divorced when he was five; and his father and stepmother, strict disciplinarians, discouraged his artistic efforts. Once he graduated high school, in Duluth, Minnesota, Bok cut off contact with his father and moved to Seattle to live with his mother. There he became active in SF fandom, including the publication and illustration of fanzines. It was in connection with these activities that he originated his pseudonym, first \"Hans\", then \"Hannes\", Bok. The pseudonym derives from Johann Sebastian Bach (whose name can be rendered both as \"Johann S. Bach\" and \"Johannes Bach\").
In 1937, Bok moved to Los Angeles, where he met Ray Bradbury. In 1938, he relocated to Seattle -- where he worked for the W.P.A. and became acquainted with artists like Mark Tobey and Morris Graves. Late in 1939, Bok moved to New York City in order to be closer to the editors and magazines which would publish his work, and where he became a member of the influential Futurians science fiction fans. Bok had corresponded with and had met Maxfield Parrish (ca. 1939?), and the influence of Parrish\'s art on Bok\'s is evident in his choice of subject matter, use of color, and application of glazes.
Bok was gay, according to his friends Forrest J Ackerman and Emil Petaja. The erotic fantasy elements of his artwork, especially his male nude subjects, display homoerotic overtones unusual for the time. The opening chapters of his novel *Beyond the Golden Stair* hint at a sexual relationship between two prison inmates, the hero John Hibbert and the gangster Frank Scarlatti.
Like his contemporary Virgil Finlay, Hannes Bok broke into commercial art and achieved initial career success as a *Weird Tales* artist -- though he did so through one of the stranger events in the history of science fiction and fantasy. In the summer of 1939, Ray Bradbury carried samples of Bok\'s art eastward to introduce his friend\'s work to magazine editors at the first World Science Fiction Convention. This was a bold move, since Bradbury was a neophyte with no connections to commercial art or the magazine industry; but it reflects the close ties within the fan and professional community. Bradbury was, at the time, a 19-year-old newspaper seller, and he borrowed funds for the trip from fellow science fiction fan Forrest J Ackerman. Bradbury succeeded; Farnsworth Wright, editor of *Weird Tales*, accepted Bok\'s art, which debuted in the December 1939 issue of *Weird Tales*. More than 50 issues of the magazine featured Bok\'s pen-and-ink work until March 1954. Bok also executed six color covers for *Weird Tales* between March 1940 and March 1942. *Weird Tales* also published five of Bok\'s stories and two of his poems between 1942 and 1951. Once he broke through into professional publications, Bok moved to New York City and lived there the rest of his life.
Throughout his life, Bok was deeply interested in astrology, as well as in the music of the Finnish composer Jean Sibelius, with whom Bok had a correspondence. (Bok\'s copy of Karl Ekman\'s *Jean Sibelius: His Life and Personality* \[Knopf, 1938\], for example, is annotated with Bok\'s comments and astrological charts.) As the years passed, Bok became prone to disagreements with editors over money and artistic issues; he grew reclusive and mystical, and preoccupied with the occult. He eked out a living, often in near poverty, until his death in 1964. He died, apparently of a heart attack (he \"starved to death\" according to Ackerman), at the age of 49. ISFDB catalogs only a few 1956 interior illustrations after March 1954, his last for *Weird Tales*, and only two cover illustrations after January 1957.
## Awards
- Hugo Award for Best Cover Artist, 1953
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# Hannes Bok
## Novels and novellas {#novels_and_novellas}
- *A Hannes Bok Treasury,* edited and an introduction by Stephen Korshak, Foreword By Ray Bradbury (Underwood-Miler), 1993
- *Starstone World* (novella), *Science Fiction Quarterly*, Summer 1942; reprinted in *The Fantastic Fiction of Hannes Bok*, American Fantasy Press, 2020.
- *The Sorcerer\'s Ship*, complete novel in the magazine *Unknown*, December 1942; reprinted as a Ballantine Adult Fantasy series paperback, 1969; reprinted in *The Fantastic Fiction of Hannes Bok*, American Fantasy Press, 2020.
- *The Fox Woman and The Blue Pagoda* (posthumous completion of the novel *The Fox Woman* by A. Merritt; also illustrated by Bok), New Collectors Group, 1946.
- *The Black Wheel* (posthumous completion of a novel by A. Merritt; also illustrated by Bok), New Collectors Group, 1947.
- *Beyond the Golden Stair* (longer version of the novella *The Blue Flamingo* in the magazine *Startling Stories*, January 1948), Ballantine Adult Fantasy series paperback, 1969; reprinted in *The Fantastic Fiction of Hannes Bok*, American Fantasy Press, 2020
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# Hen Wlad Fy Nhadau
\"***Hen Wlad Fy Nhadau***\" (`{{IPA|cy|heːn wlaːd və n̥adai̯}}`{=mediawiki}) is the unofficial national anthem of Wales. The title, taken from the first words of the song, means \"The Old Land of My Fathers\" in Welsh, usually rendered in English as simply \"**Land of My Fathers**\". The words were written by Evan James and the tune composed by his son, James James, both residents of Pontypridd, Glamorgan, in January 1856.`{{Better source needed|date=April 2024|reason=This is a news source, but is tertiary for this information. It does not cite its sources}}`{=mediawiki} The earliest written copy survives and is part of the collections of the National Library of Wales.
## History
### Origins
\"Glan Rhondda\" (\"Banks of the Rhondda\"), as it was known when it was composed, was first performed in the vestry of the original Capel Tabor, Maesteg (which later became a working men\'s club), in either January or February 1856, by Elizabeth John from Pontypridd, and it soon became popular in the locality.
James James, the composer, was a harpist who played his instrument in the public house which he ran, for the purpose of dancing. The song was originally intended to be performed in `{{music|time|6|8}}`{=mediawiki} time but had to be slowed down to its present `{{music|time|3|4}}`{=mediawiki} tempo`{{clarify|date=April 2019}}`{=mediawiki} when it began to be sung by large crowds.
### Popularity
The popularity of the song increased after the Llangollen Eisteddfod of 1858. Thomas Llewelyn of Aberdare won a competition for an unpublished collection of Welsh airs with a collection that included \"Glan Rhondda\". The adjudicator of the competition, \"Owain Alaw\" (John Owen, 1821--1883) asked for permission to include \"Glan Rhondda\" in his publication, *Gems of Welsh melody* (1860--1864). This volume gave \"Glan Rhondda\" its more famous title, \"*italic=no*\", and was sold in large quantities and ensured the popularity of the anthem across the whole of Wales.
At the Bangor Eisteddfod of 1874 \"*italic=no*\" gained further popularity when it was sung by Robert Rees (\"Eos Morlais\"), one of the leading Welsh soloists of his day. It was increasingly sung at patriotic gatherings and gradually it developed into a national anthem.
\"Hen Wlad Fy Nhadau\" was also one of the first Welsh-language songs recorded, when Madge Breese sang it on 11 March 1899, for the Gramophone Company, as part of the first recording in the Welsh language.
\"Hen Wlad Fy Nhadau\" was the first national anthem to be sung at the start of a sporting event. In 1905, the Welsh national rugby team hosted New Zealand\'s first touring team, who started every match performing a haka. As a response, Wales player Teddy Morgan led the crowd singing the anthem. Although crowds often sang anthems during games, there was no precedent for an anthem to be sung before a match.`{{refn|group=n|In the United States, singing of patriotic songs before games was first observed in the years following the [[American Civil War|Civil War]], with "[[The Star-Spangled Banner]]" occasionally being sung before baseball games. However, the song's pregame use did not become customary until the 1920s, and "The Star-Spangled Banner" did not become the official national anthem until 1931.<ref>{{cite magazine|url=https://www.espn.com/espn/story/_/id/6957582/the-history-national-anthem-sports-espn-magazine |title=The song remains the same |first1=Luke |last1=Cyphers |first2=Ethan |last2=Trex |magazine=[[ESPN The Magazine]] |date=8 September 2011 |access-date=10 April 2016}}</ref>}}`{=mediawiki}
In 1978 for their *Hen Wlad Fy Nhadau* album, Geraint Jarman a\'r Cynganeddwyr recorded a version of the anthem using electric guitars, inspired by Jimi Hendrix\'s rendition of \"The Star-Spangled Banner\" (as famously performed during the Woodstock festival in 1969 and featured in the documentary of that festival released in 1970). Jarman\'s version, played by Welsh guitarist Tich Gwilym, is one of the most famous modern versions of the song.
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# Hen Wlad Fy Nhadau
## Usage
Tradition has established \"Hen Wlad Fy Nhadau\" as a de facto Welsh national anthem since 1905, when it was first sung by fans at rugby games, although the official anthem at the time was \"God Save the King\". \"Hen Wlad Fy Nhadau\" slowly established itself as the more popular anthem over the next four decades and was sung along with \"God Bless the Prince of Wales\" and \"God Save the Queen\" before sporting events until 1975, when sports officials decided that \"Hen Wlad Fy Nhadau\" should be sung alone. Like other British anthems, it has not been established as a national anthem by law, but it has been used as a national anthem at official governmental ceremonies, including the opening of the Welsh Parliament / Senedd Cymru, and at receptions of the British monarchy since the 1970s. Petitions to make the song an official national anthem for Wales are occasionally submitted to the Senedd, but the last time one raised sufficient signatures to be debated, in 2014, the conclusion was that this is \'not currently a possible development\'. It is recognised and used as an anthem at both national and local events in Wales. `{{quote box|
''"Imagine some 40,000 people singing their national anthem with all the fervour of which the Celtic heart is capable. It was the most impressive incident I have ever witnessed on a football field. It gave a semi-religious solemnity to this memorable contest, intensely thrilling, even awe-inspiring. It was a wonderful revelation of the serious spirit in which the Welsh take their football."''
|source=All Black captain [[Dave Gallaher]]'s remark on experiencing the Welsh singing their anthem for the first time.<ref>{{cite news |last1=Hitt |first1=Carolyn |title=Our national anthem is Wales' secret weapon and a 16th player on the pitch |url=https://www.walesonline.co.uk/sport/sport-opinion/national-anthem-wales-secret-weapon-14300022 |publisher=WalesOnline |date=17 February 2018}}</ref>
|align=right|width=40%}}`{=mediawiki}
Usually, \"Hen Wlad Fy Nhadau\" will be the only anthem sung: only the first stanza and chorus are usually sung (and in the Welsh language). \"God Save the King\", the national anthem of the United Kingdom, is sometimes played alongside \"Hen Wlad Fy Nhadau\" during official events with a royal connection.
The existence of a separate national anthem for Wales has not always been apparent to those from outside the country. In 1993, the newly appointed Secretary of State for Wales, John Redwood, was embarrassingly videotaped opening and closing his mouth during a communal singing of the national anthem, clearly ignorant of the words but unable to mime convincingly; the pictures were frequently cited as evidence of his unsuitability for the post. According to John Major\'s autobiography, the first thing Redwood\'s successor William Hague said, on being appointed, was that he had better find someone to teach him the words. He found Ffion Jenkins, and later married her.
\"Hen Wlad Fy Nhadau\" has been adapted to the anthems of Cornwall (\"Bro Goth agan Tasow\"), Brittany (\"Bro Gozh ma Zadoù\"), and Y Wladfa (\"Gwlad Newydd y Cymry\", see below). These adaptations share the same tune as \"Hen Wlad Fy Nhadau\" and have similar lyrics.
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# Hen Wlad Fy Nhadau
## Lyrics
+----------------+------------------------------------------------------+-----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------+-------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------+--------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------+----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------+
| Welsh original | IPA transcription | English verse translation by A.P. Graves | English verse translation by W.S. Gwynn Williams | English verse translation by Owain Alaw | A more literal English translation |
+================+======================================================+=========================================================================================================================================================================================+=======================================================================================================================================================================================================+==================================================================================================================================================================================================+==========================================================================================================================================================================================================+
| | `{{IPA|wrap=none|'''1''' | **I** O Land of my fathers, O land of my love, Dear mother of minstrels who kindle and move, And hero on hero, who at honour\'s proud call, For freedom their lifeblood let fall. | **I** The land of my fathers is dear to me, Old land where the minstrels are honoured and free; Its warring defenders so gallant and brave, For freedom their life\'s blood they gave. | **I** Оh! Land of my fathers, the land of the free, The home of the Telyn, so soothing to me; Thy noble defenders were gallant and brave, For thy freedom their hearts\' life they gave! | **I** The old land of my fathers is dear to me, Land of bards and singers, famous men of renown; Her brave warriors, very splendid patriots, For freedom shed their blood. |
| | /maːɨ̯ heːn wlaːd və ˈn̥a.daɨ̯ ən ˈa.nʊi̯l iː miː/ | | | | |
| | /ɡwlaːd bɛi̯rð aː χanˈtɔr.jɔn ɛnˈwɔɡ.jɔn oː vriː/ | Country! Country! O but my heart is with you! As long as the sea your bulwark shall be, To Cymru my heart shall be true. | Home, home, true I am to home, While seas secure the land so pure, O may the old language endure. | Wales, Wales, my mother\'s sweet home is in Wales, Till death be pass\'d my love shall last, My longing, my hiraeth for Wales. | Country, Country, I am faithful to my Country. While the sea \[is\] a wall to the pure, most loved land, O may the old language \[*sc.* Welsh\] endure. |
| | /ɛi̯ ˈɡʊ.rɔl rəˈvɛl.wɪr ɡwladˈɡar.wɪr traː maːd/ | | | | |
| | /trɔs ˈrə.ðɪd ɡɔˈɬa.sant ɛi̯ ɡwaːɨ̯d/ | **II** O land of the mountains, the bard\'s paradise, Whose precipice, valleys are fair to my eyes, Green murmuring forest, far echoing flood Fire the fancy and quicken the blood | **II** Old land of the mountains, the Eden of bards, Each gorge and each valley a loveliness guards; Through love of my country, charmed voices will be Its streams, and its rivers, to me. | **II** Thou Eden of bards, and birthplace of song, The sons of thy mountains are valiant and strong; The voice of thy streamlets is soft to the ear, Thy hills and thy vallies how dear! | **II** Old mountainous Wales, paradise of the bard, Every valley, every cliff, to my look is beautiful. Through patriotic feeling, so charming is the murmur Of her brooks, rivers, to me. |
| | | | | | |
| | {{small|'''/ˈkət.ɡan/:'''}} | **III** For tho\' the fierce foeman has ravaged your realm, The old speech of Wales he cannot o\'erwhelm, Our passionate poets to silence command, Or banish the harp from your strand. | **III** Though foemen have trampled my land \'neath their feet, The language of Cambria still knows no retreat; The muse is not vanquished by traitor\'s fell hand, Nor silenced the harp of my land. | **III** Though trampled and crush\'d by oppression\'s foul wrong, The language of Cambria still lives on in song; The Awen survives, nor have envious tales Yet silenced the harp of dear Wales. | **III** If the enemy oppresses my land under his foot, The old language of the Welsh is as alive as ever. The muse is not hindered by the hideous hand of treason, Nor the melodious harp of my country. |
| | /ɡwlaːd ɡwlaːd ˈplɛi̯d.jɔl uːɨ̯v iːm ɡwlaːd/ | | | | |
| | /traː moːr ən vɨːr iːr bɨːr hoːf baɨ̯/ | 𝄆 `{{small|'''''Chorus'''''}}`{=mediawiki} 𝄇 | 𝄆 `{{small|'''''Chorus'''''}}`{=mediawiki} 𝄇 | 𝄆 `{{small|'''''Chorus'''''}}`{=mediawiki} 𝄇 | 𝄆 `{{small|'''''Chorus'''''}}`{=mediawiki} 𝄇 |
| | /oː ˈbə.ðɛd iːr heːn jai̯θ barˈhaɨ̯/ | | | | |
| | | | | | |
| | '''2''' | | | | |
| | /heːn ˈɡəm.rɨ̞ vəˈnə.ðɪɡ paˈra.dʊɨ̯s ə barð/ | | | | |
| | /poːb ˈdə.frɨ̞n poːb ˈklɔɡ.wɪn iːm ˈɡɔ.lʊɡ sɨːð harð/ | | | | |
| | /truːɨ̯ ˈdɛi̯m.lad ɡwladˈɡa.rɔl mɔr ˈsʊɨ̯.nɔl ɪu̯ siː/ | | | | |
| | /ɛi̯ ˈnɛn.tɨ̞ð aˈvɔ.nɨ̞ð iː viː/ | | | | |
| | | | | | |
| | {{small|'''/ˈkət.ɡan/'''}} | | | | |
| | | | | | |
| | '''3''' | | | | |
| | /ɔs ˈtrɛi̯.ʃɔð ə ˈɡɛ.lɨ̞n və ŋwlaːd tan ɛi̯ droːɨ̯d/ | | | | |
| | /maːɨ̯ heːn jai̯θ ə ˈkəm.rɨ̞ mɔr vɪu̯ aɡ ɛrˈjoːɨ̯d/ | | | | |
| | /niː ˈlɨ.dɪu̯.ɨ̞d ər ˈau̯.ɛn ɡan ˈɛr.χɨ̞ɬ laːu̯ braːd/ | | | | |
| | /naː ˈθɛ.lɨn bɛrˈsɛi̯n.jɔl və ŋwlaːd/ | | | | |
| | | | | | |
| | 𝄆 {{small|'''/ˈkət.ɡan/'''}} 𝄇}}`{=mediawiki} | | | | |
+----------------+------------------------------------------------------+-----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------+-------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------+--------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------+----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------+
## Cultural influence {#cultural_influence}
The Welsh poet Dylan Thomas is often quoted as saying \"The land of my fathers. My fathers can have it!\" in reference to Wales. However, this is misleading, as it was a villainous character in one of Thomas\' short stories that spoke this line.
Gwynfor Evans named his history of Wales *Land of my fathers: 2,000 years of Welsh history*. It was a translation of the Welsh original, *Aros Mae*.
The £1 coins minted in 1985, 1990, 1995 and 2000 with a Welsh emblem on the reverse, also bear the edge inscription PLEIDIOL WYF I\'M GWLAD (\"I am devoted to my country\"), from the refrain of \"Hen Wlad Fy Nhadau\". The new Royal Badge of Wales adopted in 2008 features this motto.
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# Hen Wlad Fy Nhadau
## \"Gwlad Newydd y Cymry\" {#gwlad_newydd_y_cymry}
A version of \"Hen Wlad Fy Nhadau\" was written by Lewis Evans, a migrant from Wales to Y Wladfa, a Welsh-speaking settlement in Patagonia, South America. The version penned by Evans is called \"Gwlad Newydd y Cymry\" (\"The New Country of the Welsh\"). \"Gwlad Newydd y Cymry\" is played to the same tune as \"Hen Wlad Fy Nhadau\".
The lyrics to \"Gwlad Newydd y Cymry\" are as follows (note that the spelling is not consistent with modern Welsh):
+----------------------------+-------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------+
| Welsh original | English translation |
+============================+=================================================================================================================================================================================================+
| *\'\'\'Cytgan\'\'\'}}}} 𝄇* | **I** Patagonia is dear to me, The new land of the noble Welsh people; True freedom we breathe in our new country, Far from the reach of oppression and betrayal: |
| | |
| | Nation \[or country\], Nation, I am faithful to my Nation. While the sun rises above the land, Oh! may the Settlement continue
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# Habermas (surname)
**Habermas** is a surname
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# HyperCard
**HyperCard** is a software application and development kit for Apple Macintosh and Apple IIGS computers. It is among the first successful hypermedia systems predating the World Wide Web.
HyperCard combines a flat-file database with a graphical, flexible, user-modifiable interface. HyperCard includes a built-in programming language called HyperTalk for manipulating data and the user interface.
This combination of features -- a database with simple form layout, flexible support for graphics, and ease of programming -- suits HyperCard for many different projects such as rapid application development of applications and databases, interactive applications with no database requirements, command and control systems, and many examples in the demoscene.
HyperCard was originally released in 1987 for \$49.95 and was included free with all new Macs sold afterwards. It was withdrawn from sale in March 2004, having received its final update in 1998 upon the return of Steve Jobs to Apple. HyperCard was not ported to Mac OS X, but can run in the Classic Environment on versions of Mac OS X that support it.
## Overview
### Design
`{{quote box | align=right | width=25% | quote=The beauty of HyperCard is that it lets people program without having to learn how to write code — what I call "programming for the rest of us". HyperCard has made it possible for people to do things they wouldn't have ever thought of doing in the past without a lot of heavy-duty programming. It's let a lot of non-programmers, like me, into that loop. | author=David Lingwood, APDA<ref name="APDA Pinpoints"/>}}`{=mediawiki}
Described by creator Bill Atkinson as a \"software erector set\",`{{r|flynn19870817}}`{=mediawiki} HyperCard is based on the concept of a \"stack\" of virtual \"cards\". Cards hold data, just as they would in a Rolodex card-filing device. Each card contains a set of interactive objects, including text fields, check boxes, buttons, and similar common graphical user interface (GUI) elements. Users browse the stack by navigating from card to card, using built-in navigation features, a powerful search mechanism, or through user-created scripts.
Users build or modify stacks by adding new cards. They place GUI objects on the cards using an interactive layout engine based on a simple drag-and-drop interface. Also, HyperCard includes prototype or template cards called backgrounds; when new cards are created they can refer to one of these background cards, which causes all of the objects on the background to \"show through\" behind the new card. This way, a stack of cards with a common layout and functionality can be created. The layout engine is similar in concept to a form as used in most rapid application development (RAD) environments such as Borland Delphi, and Microsoft Visual Basic and Visual Studio.
The database features of the HyperCard system are based on the storage of the state of all of the objects on the cards in the physical file representing the stack. The database does not exist as a separate system within the HyperCard stack; no database engine or similar construct exists. Instead, the state of any object in the system is considered to be live and editable at any time. From the HyperCard runtime\'s perspective, there is no difference between moving a text field on the card and typing into it; both operations simply change the state of the target object within the stack. Such changes are immediately saved when complete, so typing into a field causes that text to be stored to the stack\'s physical file. The system operates in a largely stateless fashion, with no need to save during operation. This is in common with many database-oriented systems, although somewhat different from document-based applications.
The final key element in HyperCard is the script, a single code-carrying element of every object within the stack. The script is a text field whose contents are interpreted in the HyperTalk language. Like any other property, the script of any object can be edited at any time and changes are saved as soon as they were complete. When the user invokes actions in the GUI, like clicking on a button or typing into a field, these actions are translated into events by the HyperCard runtime. The runtime then examines the script of the object that is the target of the event, like a button, to see if its script object contains the event\'s code, called a handler. If it does, the HyperTalk engine runs the handler; if it does not, the runtime examines other objects in the visual hierarchy.
These concepts make up the majority of the HyperCard system; stacks, backgrounds and cards provide a form-like GUI system, the stack file provides object persistence and database-like functionality, and HyperTalk allows handlers to be written for GUI events. Unlike the majority of RAD or database systems of the era, however, HyperCard combines all of these features, both user-facing and developer-facing, in a single application. This allows rapid turnaround and immediate prototyping, possibly without any coding, allowing users to author custom solutions to problems with their own personalized interface. \"Empowerment\" became a catchword as this possibility was embraced by the Macintosh community, as was the phrase \"programming for the rest of us\", that is, anyone, not just professional programmers.
It is this combination of features that also makes HyperCard a powerful hypermedia system. Users can build backgrounds to suit the needs of some system, say a rolodex, and use simple HyperTalk commands to provide buttons to move from place to place within the stack, or provide the same navigation system within the data elements of the UI, like text fields. Using these features, it is easy to build linked systems similar to hypertext links on the Web. Unlike the Web, programming, placement, and browsing are all the same tool. Similar systems have been created for HTML, but traditional Web services are considerably more heavyweight.
### HyperTalk
HyperCard contains an object-oriented scripting language called HyperTalk, which was noted for having a syntax resembling casual English language. HyperTalk language features were predetermined by the HyperCard environment, although they could be extended by the use of external functions (XFCN) and commands (XCMD), written in a compiled language. The weakly typed HyperTalk supports most standard programming structures such as \"if--then\" and \"repeat\". HyperTalk is verbose, hence its ease of use and readability. HyperTalk code segments are referred to as \"scripts.\"
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# HyperCard
## Overview
### Externals
HyperCard can be extended significantly through the use of *external command* (XCMD) and *external function* (XFCN) modules. These are code libraries packaged in a stack\'s resource fork that integrate into either the system generally or the HyperTalk language specifically; this is an early example of the plug-in concept. Unlike conventional plug-ins, these do not require separate installation before they are available for use; they can be included in a stack, where they are directly available to scripts in that stack.
During HyperCard\'s peak popularity in the late 1980s, a whole ecosystem of vendors offered thousands of these externals such as HyperTalk compilers, graphing systems, database access, Internet connectivity, and animation. Oracle offered an XCMD that allows HyperCard to directly query Oracle databases on any platform, superseded by Oracle Card. BeeHive Technologies offered a hardware interface that allows the computer to control external devices. Connected via the Apple Desktop Bus (ADB), this instrument can read the state of connected external switches or write digital outputs to a multitude of devices.
Externals allow access to the Macintosh Toolbox, which contains many lower-level commands and functions not native to HyperTalk, such as control of the serial and ADB ports.
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# HyperCard
## History
### Development
Among the earliest Macintosh programs was Rolo, a simple free-form database program that Atkinson distributed on bulletin board systems.`{{r|miller19870817}}`{=mediawiki} He created HyperCard following an LSD trip. Work for it began in March 1985 under the name of WildCard (hence its creator code of WILD). In 1986, Dan Winkler began work on HyperTalk and the name was changed to HyperCard for trademark reasons. It was released on 11 August 1987 for the first day of the MacWorld Conference & Expo in Boston, with the understanding that Atkinson would give HyperCard to Apple only if the company promised to release it for free on all Macs. Apple timed its release to coincide with Macworld to guarantee maximum publicity.
Apple chairman John Sculley said \"Hypercard opens up the Macintosh software environment in much the way the Macintosh II opened up Mac hardware\". It and MultiFinder, also announced at Macworld, would be bundled with new Macs, and \$49 each for existing customers.`{{r|flynn19870817}}`{=mediawiki}
### Launch
HyperCard was successful almost instantly. The Apple Programmer\'s and Developer\'s Association (APDA) said, \"HyperCard has been an informational feeding frenzy. From August \[1987, when it was announced\] to October our phones never stopped ringing. It was a zoo.\" Within a few months of release, there were multiple HyperCard books and a 50 disk set of public domain stacks. Apple\'s project managers found HyperCard was being used by a huge number of people, internally and externally. Bug reports and upgrade suggestions continued to flow in, demonstrating its wide variety of users. Since it was also free, it was difficult to justify dedicating engineering resources to improvements in the software. Apple and its mainstream developers understood that HyperCard\'s user empowerment could reduce the sales of ordinary shrink-wrapped products. Stewart Alsop II speculated that HyperCard might replace Finder as the shell of the Macintosh graphical user interface.
### HyperCard 2.0 {#hypercard_2.0}
In late 1989, Kevin Calhoun, then a HyperCard engineer at Apple, led an effort to upgrade the program. This resulted in HyperCard 2.0, released in 1990. The new version included an on-the-fly compiler that greatly increased performance of computationally intensive code, a new debugger and many improvements to the underlying HyperTalk language.
At the same time HyperCard 2.0 was being developed, a separate group within Apple developed and in 1991 released HyperCard IIGS, a version of HyperCard for the Apple IIGS system. Aimed mainly at the education market, HyperCard IIGS has roughly the same feature set as the 1.x versions of Macintosh HyperCard, while adding support for the color graphics abilities of the IIGS. Although *stacks* (HyperCard program documents) are not binary-compatible, a translator program (another HyperCard stack) allows them to be moved from one platform to the other.
Then, Apple decided that most of its application software packages, including HyperCard, would be the property of a wholly owned subsidiary called Claris. Many of the HyperCard developers chose to stay at Apple rather than move to Claris, causing the development team to be split. Claris attempted to create a business model where HyperCard could also generate revenues. At first the freely-distributed versions of HyperCard shipped with authoring disabled. Early versions of Claris HyperCard contain an Easter Egg: typing \"magic\" into the message box converts the player into a full HyperCard authoring environment. When this trick came to be almost universally known, they wrote a new version, HyperCard Player, which Apple distributed with the Macintosh operating system, while Claris sold the full version commercially. Many users were upset that they had to pay to use software that had traditionally been supplied free and which many considered a basic part of the Mac.
Even after HyperCard was generating revenue, Claris did little to market it. Development continued with minor upgrades, and the first failed attempt to create a third generation of HyperCard. During this period, HyperCard began losing market share. Without several important, basic features, HyperCard authors began moving to systems such as SuperCard and Macromedia Authorware. Nonetheless, HyperCard continued to be popular and used for a widening range of applications, from the game *The Manhole*, an earlier effort by the creators of *Myst*, to corporate information services.
Apple eventually folded Claris back into the parent company, returning HyperCard to Apple\'s core engineering group. In 1992, Apple released the eagerly anticipated upgrade of HyperCard 2.2 and included licensed versions of Color Tools and Addmotion II, adding support for color pictures and animations. However, these tools are limited and often cumbersome to use because HyperCard 2.0 lacks true, internal color support.
### HyperCard 3.0 {#hypercard_3.0}
Several attempts were made to restart HyperCard development once it returned to Apple. Because of the product\'s widespread use as a multimedia-authoring tool it was rolled into the QuickTime group. A new effort to allow HyperCard to create QuickTime interactive (QTi) movies started, once again under the direction of Kevin Calhoun. QTi extended QuickTime\'s core multimedia playback features to provide true interactive facilities and a low-level programming language based on 68000 assembly language. The resulting HyperCard 3.0 was first presented in 1996 when an alpha-quality version was shown to developers at Apple\'s annual Apple Worldwide Developers Conference (WWDC). Under the leadership of Dan Crow development continued through the late 1990s, with public demos showing many popular features such as color support, Internet connectivity, and the ability to play HyperCard stacks (which were now special QuickTime movies) in a web browser. Development upon HyperCard 3.0 stalled when the QuickTime team was focused away from developing QuickTime interactive to the streaming features of QuickTime 4.0. in 1998 Steve Jobs disliked the software because Atkinson had chosen to stay at Apple to finish it instead of joining Jobs at NeXT, and (according to Atkinson) \"it had Sculley\'s stink all over it\". In 2000, the HyperCard engineering team was reassigned to other tasks after Jobs decided to abandon the product. Calhoun and Crow both left Apple shortly after, in 2001.
Its final release was in 1998, and it was totally discontinued in March 2004.
HyperCard runs natively only in the classic Mac OS, but it can still be used in Mac OS X\'s Classic mode on PowerPC based machines (G5 and earlier). The last functional native HyperCard authoring environment is Classic mode in Mac OS X 10.4 (Tiger) on PowerPC-based machines.
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# HyperCard
## Applications
HyperCard has been used for a range of hypertext and artistic purposes. Before the advent of PowerPoint, HyperCard was often used as a general-purpose presentation program. Examples of HyperCard applications include simple databases, \"choose your own adventure\"-type games, and educational teaching aids.
Due to its rapid application design facilities, HyperCard was also often used for prototyping applications and sometimes even for version 1.0 implementations. Inside Apple, the QuickTime team was one of HyperCard\'s biggest customers.
HyperCard has lower hardware requirements than Macromedia Director. Several commercial software products were created in HyperCard, most notably the original version of the graphic adventure game *Myst*, the Voyager Company\'s Expanded Books, multimedia CD-ROMs of Beethoven\'s Ninth Symphony CD-ROM, *A Hard Day\'s Night* by the Beatles, and the Voyager *MacBeth*. An early electronic edition of the *Whole Earth Catalog* was implemented in HyperCard. and stored on CD-ROM.
The prototype and demo of the popular game *You Don\'t Know Jack* was written in HyperCard. The French auto manufacturer Renault used it to control their inventory system.
In Quebec, Canada, HyperCard was used to control a robot arm used to insert and retrieve video disks at the National Film Board CinéRobothèque.
In 1989, Hypercard was used to control the BBC Radiophonic Workshop Studio Network, using a single Macintosh.
HyperCard was used to prototype a fully functional prototype of SIDOCI (one of the first experiments in the world to develop an integrated electronic patient record system) and was heavily used by Montréal Consulting firm DMR to demonstrate what \"a typical day in the life of a patient about to get surgery\" would look like in a paperless age.
Activision, which was until then mainly a game company, saw HyperCard as an entry point into the business market. Changing its name to Mediagenic, it published several major HyperCard-based applications, most notably Danny Goodman\'s Focal Point, a personal information manager, and Reports For HyperCard, a program by Nine To Five Software that allows users to treat HyperCard as a full database system with robust information viewing and printing features.
The HyperCard-inspired SuperCard for a while included the *Roadster* plug-in that allowed stacks to be placed inside web pages and viewed by web browsers with an appropriate browser plug-in. There was even a Windows version of this plug-in allowing computers other than Macintoshes to use the plug-in.
### Exploits
The first HyperCard virus was discovered in Belgium and the Netherlands in April 1991.
Because HyperCard executed scripts in stacks immediately on opening, it was also one of the first applications susceptible to macro viruses. The Merryxmas virus was discovered in early 1993 by Ken Dunham, two years before the *Concept* virus. Very few viruses were based on HyperCard, and their overall impact was minimal.
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# HyperCard
## Reception
\"Hypercard Steals Show At Macworld Exposition\", *InfoWorld* reported in August 1987. The magazine said that Apple expected to put the \"unusual\" software in Macs\' ROM, and that third-party developers would create most stackware. Besides Activision and Goodman, Dialog and the Whole Earth Catalog announced stackware at the show, while Dan Bricklin said HyperCard \"seems to be the best\" hypertext software so far. The magazine\'s Michael J. Miller said \"Hypercard is unlike anything else I\'ve seen\". While predicting that many would find it useful just for the built-in applications, he concluded that \"Hypercard seems so deep and so powerful that I\'m sure I haven\'t discovered everything it\'s capable of. Yet it\'s surprisingly simple to use \... It\'s a unique program at an unbelievable price\".
Within one week, an estimated 10,000 copies had been distributed; 35,000 copies within one month. Goodman\'s on HyperCard manual, released at the same time as the software, became the best-selling Macintosh book in history.`{{r|macuser1188}}`{=mediawiki} *Compute!\'s Apple Applications* in 1987 stated that HyperCard \"may make Macintosh the personal computer of choice\". While noting that its large memory requirement made it best suited for computers with 2 MB of memory and hard drives, the magazine predicted that \"the smallest programming shop should be able to turn out stackware\", especially for using CD-ROMs. *Compute!* predicted in 1988 that most future Mac software would be developed using HyperCard, if only because using it was so addictive that developers \"won\'t be able to tear themselves away from it long enough to create anything else\". *Byte* in 1989 listed it as among the \"Excellence\" winners of the Byte Awards. While stating that \"like any first entry, it has some flaws\", the magazine wrote that \"HyperCard opened up a new category of software\", and praised Apple for bundling it with every Mac. In 2001 Steve Wozniak called HyperCard \"the best program ever written\".
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# HyperCard
## Legacy
HyperCard is one of the first products that made use of and popularized the hypertext concept to a large popular base of users.
Jakob Nielsen has pointed out that HyperCard was really only a hypermedia program since its links started from regions on a card, not text objects; actual HTML-style text hyperlinks were possible in later versions, but were awkward to implement and seldom used. Deena Larsen programmed links into HyperCard for Marble Springs. Bill Atkinson later lamented that if he had only realized the power of network-oriented stacks, instead of focusing on local stacks on a single machine, HyperCard could have become the first Web browser.
HyperCard saw a loss in popularity with the growth of the World Wide Web, since the Web could handle and deliver data in much the same way as HyperCard without being limited to files on a local hard disk. HyperCard had a significant impact on the web as it inspired the creation of both HTTP (through its influence on Tim Berners-Lee\'s colleague Robert Cailliau), and JavaScript (whose creator, Brendan Eich, was inspired by HyperTalk). It was also a key inspiration for ViolaWWW, an early web browser.
The pointing-finger cursor used for navigating stacks was later used in the first web browsers, as the hyperlink cursor.
The *Myst* computer game franchise, initially released as a HyperCard stack and included bundled with some Macs (for example the Performa 5300), still lives on, making HyperCard a facilitating technology for starting one of the best-selling computer games of all time.
According to Ward Cunningham, the inventor of Wiki, the wiki concept can be traced back to a HyperCard stack he wrote in the late 1980s.
In 2017 the Internet Archive established a project to preserve and emulate HyperCard stacks, allowing users to upload their own.
The GUI of the prototype Apple Wizzy Active Lifestyle Telephone was based on HyperCard.
### World Wide Web {#world_wide_web}
HyperCard influenced the development of the Web in late 1990 through its influence on Robert Cailliau, who assisted in developing Tim Berners-Lee\'s first Web browser. Javascript was inspired by HyperTalk.
Although HyperCard stacks do not operate over the Internet, by 1988, at least 300 stacks were publicly available for download from the commercial CompuServe network (which was not connected to the official Internet yet). The system can link phone numbers on a user\'s computer together and enable them to dial numbers without a modem, using a less expensive piece of hardware, the Hyperdialer.
In this sense, like the Web, it does form an association-based experience of information browsing via links, though not operating remotely over the TCP/IP protocol then. Like the Web, it also allows for the connections of many different kinds of media.
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# HyperCard
## Legacy
### Similar systems {#similar_systems}
Atkinson said that the odds a non-Macintosh software product would clone HyperCard were \"99 percent\", and hoped that they would be data compatible with HyperCard.`{{r|mace19870817}}`{=mediawiki} `{{As of|2024}}`{=mediawiki}, two products are available which offer HyperCard-like abilities:
- HyperStudio, one of the first HyperCard clones, is `{{as of|2009|lc=yes}}`{=mediawiki}, developed and published by Software MacKiev.
- LiveCode, published by LiveCode, Ltd., expands greatly on HyperCard\'s feature set and offers color and a GUI toolkit which can be deployed on many popular platforms (Android, iOS, Classic Macintosh system software, Mac OS X, Windows 98 through 10, and Linux/Unix). LiveCode directly imports extant HyperCard stacks and provides a migration path for stacks still in use.
Past products include:
- Guide, which preceded HyperCard. Office Workstations Limited announced immediately after HyperCard\'s debut that version 2.0 would allow HyperCard files to work on Windows.
- SuperCard, the first HyperCard clone, is similar to HyperCard, but with many added features such as full color support, pixel and vector graphics, a full GUI toolkit, and support for many modern macOS features. It can create both standalone applications and projects that run on the freeware SuperCard Player. SuperCard can also convert extant HyperCard stacks into SuperCard projects. It runs only on Macs.
- SK8 is a \"HyperCard killer\" developed within Apple but never released. It extends HyperTalk to allow arbitrary objects which allowed it to build complete Mac-like applications (instead of stacks). The project was never released, although the source code was placed in the public domain.
- Hyper DA by Symmetry is a Desk Accessory for classic single-tasked Mac OS that allows viewing HyperCard 1.x stacks as added windows in any extant application, and is also embedded into many Claris products (like MacDraw II) to display their user documentation.
- HyperPad from Brightbill-Roberts is a clone of HyperCard, written for DOS. It makes use of ASCII linedrawing to create the graphics of cards and buttons.
- Plus, later renamed WinPlus, is similar to HyperCard, for Windows and Macintosh. Oracle purchased Plus and created a cross-platform version as Oracle Card, later renamed Oracle Media Objects, used as a 4GL for database access.
- IBM LinkWay is a mouse-controlled HyperCard-like environment for DOS PCs. It has minimal system requirements, runs in graphics CGA and VGA. It even supported video disc control.
- Asymetrix\'s Windows application ToolBook resembles HyperCard, and later included an external converter to read HyperCard stacks (the first was a third-party product from Heizer software).
- TileStack is an attempt to create a web based version of HyperCard that is compatible with the original HyperCard files. The site closed down January 24, 2011.
In addition, many of the basic concepts of the original system were later re-used in other forms. Apple built its system-wide scripting engine AppleScript on a language similar to HyperTalk; it is often used for desktop publishing (DTP) workflow automation needs. In the 1990s FaceSpan provided a third-party graphical interface. AppleScript also has a native graphical programming front-end called Automator, released with Mac OS X Tiger in April 2005. One of HyperCard\'s strengths was its handling of multimedia, and many multimedia systems like Macromedia Authorware and Macromedia Director are based on concepts originating in HyperCard.
AppWare, originally named Serius Developer, is sometimes seen to be similar to HyperCard, as both are rapid application development (RAD) systems. AppWare was sold in the early 90s and worked on both Mac and Windows systems.
Zoomracks, a DOS application with a similar \"stack\" database metaphor, predates HyperCard by four years, which led to a contentious lawsuit against Apple
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# Harthouse
**Harthouse** is a German record label specializing in techno music.
The company was founded by Sven Väth in the early 1990s as a sublabel of Eye Q Records with the divisions Harthouse Frankfurt, Harthouse UK and Harthouse America.
In the beginning of 1997 the future of the label was uncertain, sales were dropping in the wake of rising commercial trance labels, and Sven Väth had left the label in January, causing further confusion. The firm moved from its office in Offenbach to Berlin. Two months later the firm was insolvent, and filed for bankruptcy.
At the beginning of 1998 the Under Cover Music Group (UCMG) took over the rights to use the brand name of the label as well as the trademark Harthouse. UCMG put together a *Retrospective Box*, a collection of the most successful releases of Harthouse.
Between 1998 and 2003, there were only several new releases.
In early 2003, UCMG started to get into financial problems. In the middle of 2003 Harthouse planned to re-release a set of old classic singles, but after some test vinyl was pressed, UCMG was closed.
In 2004 Daredo Music took over the rights of the Harthouse brand
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# Heteroatom
thumb\|right\|upright=0.5\|Pyridine is a heterocyclic compound and the heteroatom is nitrogen.
In chemistry, a **heteroatom** (`{{ety|grc|heteros|different||atomos|uncut}}`{=mediawiki}) is, strictly, any atom that is not carbon or hydrogen.
## Organic chemistry {#organic_chemistry}
In practice, the term is mainly used more specifically to indicate that non-carbon atoms have replaced carbon in the backbone of the molecular structure. Typical heteroatoms are nitrogen (N), oxygen (O), sulfur (S), phosphorus (P), chlorine (Cl), bromine (Br), and iodine (I), as well as the metals lithium (Li) and magnesium (Mg).
## Proteins
It can also be used with highly specific meanings in specialised contexts. In the description of protein structure, in particular in the Protein Data Bank file format, a heteroatom record (HETATM) describes an atom as belonging to a small molecule cofactor rather than being part of a biopolymer chain.
## Zeolites
In the context of zeolites, the term *heteroatom* refers to partial isomorphous substitution of the typical framework atoms (silicon, aluminium, and phosphorus) by other elements such as beryllium, vanadium, and chromium. The goal is usually to adjust properties of the material (e.g., Lewis acidity) to optimize the material for a certain application (e.g., catalysis)
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# Half-life
+-------------+-----------+-------------+
| Number of\ | Fraction\ | Percentage\ |
| half-lives\ | remaining | remaining |
| elapsed | | |
+=============+===========+=============+
| 0 | | 100 |
+-------------+-----------+-------------+
| 1 | | 50 |
+-------------+-----------+-------------+
| 2 | | 25 |
+-------------+-----------+-------------+
| 3 | | 12 |
+-------------+-----------+-------------+
| 4 | | 6 |
+-------------+-----------+-------------+
| 5 | | 3 |
+-------------+-----------+-------------+
| 6 | | 1 |
+-------------+-----------+-------------+
| 7 | | 0 |
+-------------+-----------+-------------+
| | | |
+-------------+-----------+-------------+
| | | |
+-------------+-----------+-------------+
**Half-life** (symbol `{{math|'''''t''{{sub|½}}'''}}`{=mediawiki}) is the time required for a quantity (of substance) to reduce to half of its initial value. The term is commonly used in nuclear physics to describe how quickly unstable atoms undergo radioactive decay or how long stable atoms survive. The term is also used more generally to characterize any type of exponential (or, rarely, non-exponential) decay. For example, the medical sciences refer to the biological half-life of drugs and other chemicals in the human body. The converse of half-life (in exponential growth) is doubling time.
The original term, *half-life period*, dating to Ernest Rutherford\'s discovery of the principle in 1907, was shortened to *half-life* in the early 1950s. Rutherford applied the principle of a radioactive element\'s half-life in studies of age determination of rocks by measuring the decay period of radium to lead-206.
Half-life is constant over the lifetime of an exponentially decaying quantity, and it is a characteristic unit for the exponential decay equation. The accompanying table shows the reduction of a quantity as a function of the number of half-lives elapsed.
## Probabilistic nature {#probabilistic_nature}
A half-life often describes the decay of discrete entities, such as radioactive atoms. In that case, it does not work to use the definition that states \"half-life is the time required for exactly half of the entities to decay\". For example, if there is just one radioactive atom, and its half-life is one second, there will *not* be \"half of an atom\" left after one second.
Instead, the half-life is defined in terms of probability: \"Half-life is the time required for exactly half of the entities to decay *on average*\". In other words, the *probability* of a radioactive atom decaying within its half-life is 50%.
For example, the accompanying image is a simulation of many identical atoms undergoing radioactive decay. Note that after one half-life there are not *exactly* one-half of the atoms remaining, only *approximately*, because of the random variation in the process. Nevertheless, when there are many identical atoms decaying (right boxes), the law of large numbers suggests that it is a *very good approximation* to say that half of the atoms remain after one half-life.
Various simple exercises can demonstrate probabilistic decay, for example involving flipping coins or running a statistical computer program.
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# Half-life
## Formulas for half-life in exponential decay {#formulas_for_half_life_in_exponential_decay}
An exponential decay can be described by any of the following four equivalent formulas:$\begin{align}
N(t) &= N_0 \left(\frac {1}{2}\right)^{\frac{t}{t_{1/2}}} \\
N(t) &= \left(2^{-\frac{t}{t_{1/2}}}\right) N_0 \\
N(t) &= N_0 e^{-\frac{t}{\tau}} \\
N(t) &= N_0 e^{-\lambda t}
\end{align}$ where
- is the initial quantity of the substance that will decay (this quantity may be measured in grams, moles, number of atoms, etc.),
- is the quantity that still remains and has not yet decayed after a time `{{mvar|t}}`{=mediawiki},
- is the half-life of the decaying quantity,
- is a positive number called the mean lifetime of the decaying quantity,
- is a positive number called the decay constant of the decaying quantity.
The three parameters `{{math|''t''{{sub|½}}}}`{=mediawiki}, `{{mvar|τ}}`{=mediawiki}, and `{{mvar|λ}}`{=mediawiki} are directly related in the following way$$t_{1/2} = \frac{\ln (2)}{\lambda} = \tau \ln(2)$$where `{{math|ln(2)}}`{=mediawiki} is the natural logarithm of 2 (approximately 0.693).
### Half-life and reaction orders {#half_life_and_reaction_orders}
In chemical kinetics, the value of the half-life depends on the reaction order:
#### Zero order kinetics {#zero_order_kinetics}
The rate of this kind of reaction does not depend on the substrate concentration, `{{math|[A]}}`{=mediawiki}. Thus the concentration decreases linearly.
: $d[\ce A]/dt = - k$The integrated rate law of zero order kinetics is:
$[\ce A] = [\ce A]_0 - kt$In order to find the half-life, we have to replace the concentration value for the initial concentration divided by 2: $[\ce A]_{0}/2 = [\ce A]_0 - kt_{1/2}$and isolate the time$$t_{1/2} = \frac{[\ce A]_0}{2k}$$This `{{math|''t''{{sub|½}}}}`{=mediawiki} formula indicates that the half-life for a zero order reaction depends on the initial concentration and the rate constant.
#### First order kinetics {#first_order_kinetics}
In first order reactions, the rate of reaction will be proportional to the concentration of the reactant. Thus the concentration will decrease exponentially. $[\ce A] = [\ce A]_0 \exp(-kt)$as time progresses until it reaches zero, and the half-life will be constant, independent of concentration.
The time `{{math|''t''{{sub|½}}}}`{=mediawiki} for `{{math|[A]}}`{=mediawiki} to decrease from `{{math|[A]{{sub|0}}}}`{=mediawiki} to `{{math|{{sfrac|1|2}}[A]{{sub|0}}}}`{=mediawiki} in a first-order reaction is given by the following equation$$[\ce A]_0 /2 = [\ce A]_0 \exp(-kt_{1/2})$$It can be solved for$kt_{1/2} = -\ln \left(\frac{[\ce A]_0 /2}{[\ce A]_0}\right) = -\ln\frac{1}{2} = \ln 2$For a first-order reaction, the half-life of a reactant is independent of its initial concentration. Therefore, if the concentration of `{{math|A}}`{=mediawiki} at some arbitrary stage of the reaction is `{{math|[A]}}`{=mediawiki}, then it will have fallen to `{{math|{{sfrac|1|2}}[A]}}`{=mediawiki} after a further interval of `{{tmath|\tfrac{\ln 2}{k}.}}`{=mediawiki} Hence, the half-life of a first order reaction is given as the following:
$t_{1/2} = \frac{\ln 2}{k}$The half-life of a first order reaction is independent of its initial concentration and depends solely on the reaction rate constant, `{{mvar|k}}`{=mediawiki}.
#### Second order kinetics {#second_order_kinetics}
In second order reactions, the rate of reaction is proportional to the square of the concentration. By integrating this rate, it can be shown that the concentration `{{math|[A]}}`{=mediawiki} of the reactant decreases following this formula:
$\frac{1}{[\ce A]} = kt + \frac{1}{[\ce A]_0}$We replace `{{math|[A]}}`{=mediawiki} for `{{math|{{sfrac|1|2}}{{math|[A]}}{{sub|0}}}}`{=mediawiki} in order to calculate the half-life of the reactant `{{math|A}}`{=mediawiki} $\frac{1}{[\ce A]_0 /2} = kt_{1/2} + \frac{1}{[\ce A]_0}$and isolate the time of the half-life (`{{math|''t''{{sub|½}}}}`{=mediawiki})$$t_{1/2} = \frac{1}{[\ce A]_0 k}$$This shows that the half-life of second order reactions depends on the initial concentration and rate constant.
### Decay by two or more processes {#decay_by_two_or_more_processes}
Some quantities decay by two exponential-decay processes simultaneously. In this case, the actual half-life `{{math|''T''{{sub|½}}}}`{=mediawiki} can be related to the half-lives `{{math|''t''{{sub|1}}}}`{=mediawiki} and `{{math|''t''{{sub|2}}}}`{=mediawiki} that the quantity would have if each of the decay processes acted in isolation: $\frac{1}{T_{1/2}} = \frac{1}{t_1} + \frac{1}{t_2}$
For three or more processes, the analogous formula is: $\frac{1}{T_{1/2}} = \frac{1}{t_1} + \frac{1}{t_2} + \frac{1}{t_3} + \cdots$ For a proof of these formulas, see Exponential decay § Decay by two or more processes.
### Examples
There is a half-life describing any exponential-decay process. For example:
- As noted above, in radioactive decay the half-life is the length of time after which there is a 50% chance that an atom will have undergone nuclear decay. It varies depending on the atom type and isotope, and is usually determined experimentally. See List of nuclides.
- The current flowing through an RC circuit or RL circuit decays with a half-life of `{{math|ln(2)''RC''}}`{=mediawiki} or `{{math|ln(2)''L''/''R''}}`{=mediawiki}, respectively. For this example the term half time tends to be used rather than \"half-life\", but they mean the same thing.
- In a chemical reaction, the half-life of a species is the time it takes for the concentration of that substance to fall to half of its initial value. In a first-order reaction the half-life of the reactant is `{{math|ln(2)/''λ''}}`{=mediawiki}, where `{{mvar|λ}}`{=mediawiki} (also denoted as `{{mvar|k}}`{=mediawiki}) is the reaction rate constant.
## In non-exponential decay {#in_non_exponential_decay}
The term \"half-life\" is almost exclusively used for decay processes that are exponential (such as radioactive decay or the other examples above), or approximately exponential (such as biological half-life discussed below). In a decay process that is not even close to exponential, the half-life will change dramatically while the decay is happening. In this situation it is generally uncommon to talk about half-life in the first place, but sometimes people will describe the decay in terms of its \"first half-life\", \"second half-life\", etc., where the first half-life is defined as the time required for decay from the initial value to 50%, the second half-life is from 50% to 25%, and so on.
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# Half-life
## In biology and pharmacology {#in_biology_and_pharmacology}
A biological half-life or elimination half-life is the time it takes for a substance (drug, radioactive nuclide, or other) to lose one-half of its pharmacologic, physiologic, or radiological activity. In a medical context, the half-life may also describe the time that it takes for the concentration of a substance in blood plasma to reach one-half of its steady-state value (the \"plasma half-life\").
The relationship between the biological and plasma half-lives of a substance can be complex, due to factors including accumulation in tissues, active metabolites, and receptor interactions.
While a radioactive isotope decays almost perfectly according to first order kinetics, where the rate constant is a fixed number, the elimination of a substance from a living organism usually follows more complex chemical kinetics.
For example, the biological half-life of water in a human being is about 9 to 10 days, though this can be altered by behavior and other conditions. The biological half-life of caesium in human beings is between one and four months.
The concept of a half-life has also been utilized for pesticides in plants, and certain authors maintain that pesticide risk and impact assessment models rely on and are sensitive to information describing dissipation from plants.
In epidemiology, the concept of half-life can refer to the length of time for the number of incident cases in a disease outbreak to drop by half, particularly if the dynamics of the outbreak can be modeled exponentially
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# Hardware (mechanical and construction)
**Hardware** (some types also known as **household hardware**) is equipment, generally used in machines, in construction or in any built good, that can be touched or held by hand such as keys, locks, nuts, screws, washers, hinges, latches, handles, wire, chains, belts, plumbing supplies, electrical supplies, tools, utensils, cutlery and machine parts. Household hardware is typically sold in hardware stores
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# Hugo Gernsback
thumb\|right \|Gernsback watching a television broadcast by his station WRNY on the cover of his *Radio News* (Nov 1928)
**Hugo Gernsback** (`{{IPAc-en|ˈ|g|ɜr|n|z|b|æ|k}}`{=mediawiki}; born **Hugo Gernsbacher**, August 16, 1884 -- August 19, 1967) was a Luxembourgish American editor and magazine publisher whose publications included the first science fiction magazine, *Amazing Stories*. His contributions to the genre as publisher were so significant that, along with the novelists Jules Verne and H. G. Wells, he is sometimes called \"The Father of Science Fiction\". In his honor, annual awards presented at the World Science Fiction Convention are named the \"Hugos\".
Gernsback emigrated to the U.S. in 1904 and later became a citizen. He was also a significant figure in the electronics and radio industries, even starting a radio station, WRNY, and the world\'s first magazine about electronics and radio, *Modern Electrics*. Gernsback died in New York City in 1967.
## Personal life {#personal_life}
Gernsback was born in 1884 in Luxembourg City, to Berta (Dürlacher), a housewife, and Moritz Gernsbacher, a winemaker. His family was Jewish. Gernsback emigrated to the United States in 1904 and later became a naturalized citizen. He married three times: to Rose Harvey in 1906, Dorothy Kantrowitz in 1921, and Mary Hancher (1914--1985) in 1951. In 1925, he founded radio station WRNY, which was broadcast from the 18th floor of the Roosevelt Hotel in New York City. In 1928, WRNY aired some of the first television broadcasts. During the show, audio stopped and each artist waved or bowed onscreen. When audio resumed, they performed. Gernsback is also considered a pioneer in amateur radio.
Before helping to create science fiction, Gernsback was an entrepreneur in the electronics industry, importing radio parts from Europe to the United States and helping to popularize amateur \"wireless\". In April 1908 he founded *Modern Electrics*, the world\'s first magazine about both electronics and radio, called \"wireless\" at the time. While the cover of the magazine itself states it was a catalog, most historians note that it contained articles, features, and plotlines, qualifying it as a magazine.
Under its auspices, in January 1909, he founded the Wireless Association of America, which had 10,000 members within a year. In 1912, Gernsback said that he estimated 400,000 people in the U.S. were involved in amateur radio. In 1913, he founded a similar magazine, *The Electrical Experimenter*, which became *Science and Invention* in 1920. It was in these magazines that he began including scientific fiction stories alongside science journalism, including his novel *Ralph 124C 41+*, which he ran for 12 months from April 1911 in *Modern Electrics*.
Hugo Gernsback started the *Radio News* magazine for amateur radio enthusiasts in 1919.
He died at Roosevelt Hospital (Mount Sinai West as of 2020) in New York City on August 19, 1967, at age 83.
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# Hugo Gernsback
## Science fiction {#science_fiction}
Gernsback provided a forum for the modern genre of science fiction in 1926 by founding the first magazine dedicated to it, *Amazing Stories*. The inaugural April issue comprised a one-page editorial and reissues of six stories, three less than ten years old and three by Poe, Verne, and Wells. He said he became interested in the concept after reading a translation of the work of Percival Lowell as a child. His idea of a perfect science fiction story was \"75 percent literature interwoven with 25 percent science\". As an editor, he valued the goal of scientific accuracy in science fiction stories: \"Not only did Gernsback establish a panel of experts------all reputable professionals from universities, museums, and institutes---to pass judgment on the accuracy of the science; he also encouraged his writers to elaborate on the scientific details they employed in their stories, comment on the impossibilities in each other\'s stories, and even offered his readers prize money for identifying scientific errors.\" He also played an important role in starting science fiction fandom, by organizing the Science Fiction League and by publishing the addresses of people who wrote letters to his magazines. Fans began to organize, and became aware of themselves as a movement, a social force; this was probably decisive for the subsequent history of the genre.
Gernsback created his preferred term for the emerging genre, \"scientifiction\", in 1916. He is sometimes also credited with coining \"science fiction\" in 1929 in the preface of the first *Science Wonder Stories*, although instances of \"science-fiction\" (mostly, but not always, hyphenated) have been found as far back as 1851, and the preface itself makes no mention of it being a new term.
In 1929, he lost ownership of his first magazines after a bankruptcy lawsuit. There is some debate about whether this process was genuine, manipulation by publisher Bernarr Macfadden, or a Gernsback scheme to begin another company. After losing control of *Amazing Stories*, Gernsback founded two new science fiction magazines, *Science Wonder Stories* and *Air Wonder Stories*. A year later, due to Depression-era financial troubles, the two were merged into *Wonder Stories*, which Gernsback continued to publish until 1936, when it was sold to Thrilling Publications and renamed *Thrilling Wonder Stories*. Gernsback returned in 1952--53 with *Science-Fiction Plus*.
Gernsback was noted for sharp, sometimes shady, business practices, and for paying his writers extremely low fees or not paying them at all. H. P. Lovecraft and Clark Ashton Smith referred to him as \"Hugo the Rat\".
Barry Malzberg has said:
> Gernsback\'s venality and corruption, his sleaziness and his utter disregard for the financial rights of authors, have been well documented and discussed in critical and fan literature. That the founder of genre science fiction who gave his name to the field\'s most prestigious award and who was the Guest of Honor at the 1952 Worldcon was pretty much a crook (and a contemptuous crook who stiffed his writers but paid himself \$100K a year as President of Gernsback Publications) has been clearly established.
Jack Williamson, who had to hire an attorney associated with the American Fiction Guild to force Gernsback to pay him, summed up his importance for the genre:
> At any rate, his main influence in the field was simply to start Amazing and Wonder Stories and get SF out to the public newsstands---and to name the genre he had earlier called \"scientifiction.\"
## Fiction
Frederik Pohl said in 1965 that Gernsback\'s *Amazing Stories* published \"the kind of stories Gernsback himself used to write: a sort of animated catalogue of gadgets\". Gernsback\'s fiction includes the novel *Ralph 124C 41+*; the title is a pun on the phrase \"one to foresee for many\" (\"one plus\"). Even though *Ralph 124C 41+* has been described as pioneering many ideas and themes found in later SF work, it has often been neglected due to what most critics deem poor artistic quality. Author Brian Aldiss called the story a \"tawdry illiterate tale\" and a \"sorry concoction\", while author and editor Lester del Rey called it \"simply dreadful.\" While most other modern critics have little positive to say about the story\'s writing, *Ralph 124C 41+* is considered by science fiction critic Gary Westfahl as \"essential text for all studies of science fiction.\"
Gernsback\'s second novel, *Baron Münchausen\'s Scientific Adventures*, was serialized in *Amazing Stories* in 1928.
Gernsback\'s third (and final) novel, *Ultimate World*, written c. 1958, was not published until 1971. Lester del Rey described it simply as \"a bad book\", marked more by routine social commentary than by scientific insight or extrapolation. James Blish, in a caustic review, described the novel as \"incompetent, pedantic, graceless, incredible, unpopulated and boring\" and concluded that its publication \"accomplishes nothing but the placing of a blot on the memory of a justly honored man.\"
Gernsback combined his fiction and science into *Everyday Science and Mechanics* magazine, serving as the editor in the 1930s.
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# Hugo Gernsback
## Legacy
In 1954, Gernsback was awarded an Officer of Luxembourg\'s Order of the Oak Crown, an honor equivalent to being knighted.
The Hugo Awards or \"Hugos\" are the annual achievement awards presented at the World Science Fiction Convention, selected in a process that ends with vote by current Convention members. They originated and acquired the \"Hugo\" nickname during the 1950s and were formally defined as a convention responsibility under the name \"Science Fiction Achievement Awards\" early in the 1960s. The nickname soon became almost universal and its use legally protected; \"Hugo Award(s)\" replaced the longer name in all official uses after the 1991 cycle.
In 1960 Gernsback received a special Hugo Award as \"The Father of Magazine Science Fiction\".
The Science Fiction and Fantasy Hall of Fame inducted him in 1996, its inaugural class of two deceased and two living persons.
Science fiction author Brian W. Aldiss held a contrary view about Gernsback\'s contributions: \"It is easy to argue that Hugo Gernsback \... was one of the worst disasters to hit the science fiction field \... Gernsback himself was utterly without any literary understanding. He created dangerous precedents which many later editors in the field followed.\"
Gernsback made significant contributions to the growth of early broadcasting, mostly through his efforts as a publisher. He originated the industry of specialized publications for radio with *Modern Electrics* and *Electrical Experimenter*. Later on, and more influentially, he published *Radio News*, which would have the largest readership among radio magazines in radio broadcasting\'s formative years. He edited *Radio News* until 1929. For a short time he hired John F. Rider to be editor. Rider was a former engineer working with the US Army Signal Corps and a radio engineer for Alfred H. Grebe, a radio manufacturer. However, Rider would soon leave Gernsback and form his own publishing company, John F. Rider Publisher, New York around 1931.
Gernsback made use of the magazine to promote his interests, including having his radio station\'s call letters on the cover starting in 1925. WRNY and *Radio News* were used to cross-promote each other, with programs on his station often used to discuss articles he had published, and articles in the magazine often covering program activities at WRNY. He also advocated for future directions in innovation and regulation of radio. The magazine contained many drawings and diagrams, encouraging radio listeners of the 1920s to experiment themselves to improve the technology. WRNY was often used as a laboratory to see if various radio inventions were worthwhile.
Articles that were published about television were also tested in this manner when the radio station was used to send pictures to experimental television receivers in August 1928. The technology, however, required sending sight and sound one after the other rather than sending both at the same time, as WRNY only broadcast on one channel. Such experiments were expensive, eventually contributing to Gernsback\'s Experimenter Publishing Company going into bankruptcy in 1929. WRNY was sold to Aviation Radio, who maintained the channel part-time to broadcast aviation weather reports and related feature programs. Along with other stations sharing the same frequency, it was acquired by Metro-Goldwyn-Mayer and consolidated into that company\'s WHN in 1934.
In 2020, Eric Schockmel directed the documentary feature film *Tune Into the Future*, which explores the life of Hugo Gernsback.
## Patents and inventions {#patents_and_inventions}
Gernsback held 80 patents by the time of his death in New York City on August 19, 1967.
His first patent was a new method for manufacturing dry cell batteries, a patent applied for on June 28, 1906, and granted February 5, 1907.
Among his inventions are a combined electric hair brush and comb (`{{US Patent|1,016,138}}`{=mediawiki}), 1912; an ear cushion (`{{US Patent|1,514,152}}`{=mediawiki}) in 1927; and a hydraulic fishery (`{{US Patent|2,718,083}}`{=mediawiki}), in 1955.
Gernsback published a work entitled *Music for the Deaf* in *The Electrical Experimenter* describing the Physiophone, a device which converted audio into electrical impulses that could be detected by humans. He advocated this device as a method for allowing the deaf to experience music.
Other patents held by Gernsback are related to: Incandescent Lamp, Electrorheostat Regulator, Electro Adjustable Condenser, Detectorium, Relay, Potentiometer, Electrolytic Interrupter, Rotary Variable Condenser, Luminous Electric Mirror, Transmitter, Postal Card, Telephone Headband, Electromagnetic Sounding Device, Submersible Amusement Device, The Isolator, Apparatus for Landing Flying Machines, Tuned Telephone Receiver, Electric Valve, Detector, Acoustic Apparatus, Electrically Operated Fountain, Cord Terminal, Coil Mounting, Radio Horn, Variable Condenser, Switch, Telephone Receiver, Crystal Detector, Process for Mounting Inductances, Depilator, Code Learner\'s Instrument
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# Hausdorff space
In topology and related branches of mathematics, a **Hausdorff space** (`{{IPAc-en|ˈ|h|aʊ|s|d|ɔːr|f}}`{=mediawiki} `{{Respell|HOWSS|dorf}}`{=mediawiki}, `{{IPAc-en|ˈ|h|aʊ|z|d|ɔːr|f}}`{=mediawiki} `{{Respell|HOWZ|dorf}}`{=mediawiki}), **T~2~ space** or **separated space**, is a topological space where distinct points have disjoint neighbourhoods. Of the many separation axioms that can be imposed on a topological space, the \"Hausdorff condition\" (T~2~) is the most frequently used and discussed. It implies the uniqueness of limits of sequences, nets, and filters.
Hausdorff spaces are named after Felix Hausdorff, one of the founders of topology. Hausdorff\'s original definition of a topological space (in 1914) included the Hausdorff condition as an axiom.
## Definitions
Points $x$ and $y$ in a topological space $X$ can be *separated by neighbourhoods* if there exists a neighbourhood $U$ of $x$ and a neighbourhood $V$ of $y$ such that $U$ and $V$ are disjoint $(U\cap V=\varnothing)$. $X$ is a **Hausdorff space** if any two distinct points in $X$ are separated by neighbourhoods. This condition is the third separation axiom (after T~0~ and T~1~), which is why Hausdorff spaces are also called **T~2~ spaces**. The name *separated space* is also used.
A related, but weaker, notion is that of a **preregular space**. $X$ is a preregular space if any two topologically distinguishable points can be separated by disjoint neighbourhoods. A preregular space is also called an **R~1~ space**.
The relationship between these two conditions is as follows. A topological space is Hausdorff if and only if it is both preregular (i.e. topologically distinguishable points are separated by neighbourhoods) and Kolmogorov (i.e. distinct points are topologically distinguishable). A topological space is preregular if and only if its Kolmogorov quotient is Hausdorff.
## Equivalences
For a topological space *$X$*, the following are equivalent:
- $X$ is a Hausdorff space.
- Limits of nets in *$X$* are unique.
- Limits of filters on *$X$* are unique.
- Any singleton set $\{ x \} \subset X$ is equal to the intersection of all closed neighbourhoods of *$x$*. (A closed neighbourhood of $x$ is a closed set that contains an open set containing $x$.)
- The diagonal *$\Delta = \{ (x, x) \mid x \in X \}$* is closed as a subset of the product space *$X \times X$*.
- Any injection from the discrete space with two points to *$X$* has the lifting property with respect to the map from the finite topological space with two open points and one closed point to a single point.
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# Hausdorff space
## Examples of Hausdorff and non-Hausdorff spaces {#examples_of_hausdorff_and_non_hausdorff_spaces}
Almost all spaces encountered in analysis are Hausdorff; most importantly, the real numbers (under the standard metric topology on real numbers) are a Hausdorff space. More generally, all metric spaces are Hausdorff. In fact, many spaces of use in analysis, such as topological groups and topological manifolds, have the Hausdorff condition explicitly stated in their definitions.
A simple example of a topology that is T~1~ but is not Hausdorff is the cofinite topology defined on an infinite set, as is the cocountable topology defined on an uncountable set.
Pseudometric spaces typically are not Hausdorff, but they are preregular, and their use in analysis is usually only in the construction of Hausdorff gauge spaces. Indeed, when analysts run across a non-Hausdorff space, it is still probably at least preregular, and then they simply replace it with its Kolmogorov quotient, which is Hausdorff.
In contrast, non-preregular spaces are encountered much more frequently in abstract algebra and algebraic geometry, in particular as the Zariski topology on an algebraic variety or the spectrum of a ring. They also arise in the model theory of intuitionistic logic: every complete Heyting algebra is the algebra of open sets of some topological space, but this space need not be preregular, much less Hausdorff, and in fact usually is neither. The related concept of Scott domain also consists of non-preregular spaces.
While the existence of unique limits for convergent nets and filters implies that a space is Hausdorff, there are non-Hausdorff T~1~ spaces in which every convergent sequence has a unique limit. Such spaces are called *US spaces*. For sequential spaces, this notion is equivalent to being weakly Hausdorff.
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# Hausdorff space
## Properties
Subspaces and products of Hausdorff spaces are Hausdorff, but quotient spaces of Hausdorff spaces need not be Hausdorff. In fact, *every* topological space can be realized as the quotient of some Hausdorff space.
Hausdorff spaces are T~1~, meaning that each singleton is a closed set. Similarly, preregular spaces are R~0~. Every Hausdorff space is a Sober space although the converse is in general not true.
Another property of Hausdorff spaces is that each compact set is a closed set. For non-Hausdorff spaces, it can be that each compact set is a closed set (for example, the cocountable topology on an uncountable set) or not (for example, the cofinite topology on an infinite set and the Sierpiński space).
The definition of a Hausdorff space says that points can be separated by neighborhoods. It turns out that this implies something which is seemingly stronger: in a Hausdorff space every pair of disjoint compact sets can also be separated by neighborhoods, in other words there is a neighborhood of one set and a neighborhood of the other, such that the two neighborhoods are disjoint. This is an example of the general rule that compact sets often behave like points.
Compactness conditions together with preregularity often imply stronger separation axioms. For example, any locally compact preregular space is completely regular. Compact preregular spaces are normal, meaning that they satisfy Urysohn\'s lemma and the Tietze extension theorem and have partitions of unity subordinate to locally finite open covers. The Hausdorff versions of these statements are: every locally compact Hausdorff space is Tychonoff, and every compact Hausdorff space is normal Hausdorff.
The following results are some technical properties regarding maps (continuous and otherwise) to and from Hausdorff spaces.
Let *$f\colon X \to Y$* be a continuous function and suppose $Y$ is Hausdorff. Then the graph of *$f$*, $\{(x,f(x)) \mid x\in X\}$, is a closed subset of *$X \times Y$*.
Let *$f\colon X \to Y$* be a function and let $\ker(f) \triangleq \{(x,x') \mid f(x) = f(x')\}$ be its kernel regarded as a subspace of *$X \times X$*.
- If *$f$* is continuous and *$Y$* is Hausdorff then *$\ker(f)$* is a closed set.
- If *$f$* is an open surjection and *$\ker(f)$* is a closed set then *$Y$* is Hausdorff.
- If *$f$* is a continuous, open surjection (i.e. an open quotient map) then *$Y$* is Hausdorff if and only if *$\ker(f)$* is a closed set.
If *$f, g \colon X \to Y$* are continuous maps and *$Y$* is Hausdorff then the equalizer $\mbox{eq}(f,g) = \{x \mid f(x) = g(x)\}$ is a closed set in *$X$*. It follows that if *$Y$* is Hausdorff and *$f$* and *$g$* agree on a dense subset of *$X$* then *$f = g$*. In other words, continuous functions into Hausdorff spaces are determined by their values on dense subsets.
Let *$f\colon X \to Y$* be a closed surjection such that *$f^{-1} (y)$* is compact for all *$y \in Y$*. Then if *$X$* is Hausdorff so is *$Y$*.
Let *$f\colon X \to Y$* be a quotient map with *$X$* a compact Hausdorff space. Then the following are equivalent:
- *$Y$* is Hausdorff.
- *$f$* is a closed map.
- *$\ker(f)$* is a closed set.
## Preregularity versus regularity {#preregularity_versus_regularity}
All regular spaces are preregular, as are all Hausdorff spaces. There are many results for topological spaces that hold for both regular and Hausdorff spaces. Most of the time, these results hold for all preregular spaces; they were listed for regular and Hausdorff spaces separately because the idea of preregular spaces came later. On the other hand, those results that are truly about regularity generally do not also apply to nonregular Hausdorff spaces.
There are many situations where another condition of topological spaces (such as paracompactness or local compactness) will imply regularity if preregularity is satisfied. Such conditions often come in two versions: a regular version and a Hausdorff version. Although Hausdorff spaces are not, in general, regular, a Hausdorff space that is also (say) locally compact will be regular, because any Hausdorff space is preregular. Thus from a certain point of view, it is really preregularity, rather than regularity, that matters in these situations. However, definitions are usually still phrased in terms of regularity, since this condition is better known than preregularity.
See History of the separation axioms for more on this issue.
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# Hausdorff space
## Variants
The terms \"Hausdorff\", \"separated\", and \"preregular\" can also be applied to such variants on topological spaces as uniform spaces, Cauchy spaces, and convergence spaces. The characteristic that unites the concept in all of these examples is that limits of nets and filters (when they exist) are unique (for separated spaces) or unique up to topological indistinguishability (for preregular spaces).
As it turns out, uniform spaces, and more generally Cauchy spaces, are always preregular, so the Hausdorff condition in these cases reduces to the T~0~ condition. These are also the spaces in which completeness makes sense, and Hausdorffness is a natural companion to completeness in these cases. Specifically, a space is complete if and only if every Cauchy net has at *least* one limit, while a space is Hausdorff if and only if every Cauchy net has at *most* one limit (since only Cauchy nets can have limits in the first place).
## Algebra of functions {#algebra_of_functions}
The algebra of continuous (real or complex) functions on a compact Hausdorff space is a commutative C\*-algebra, and conversely by the Banach--Stone theorem one can recover the topology of the space from the algebraic properties of its algebra of continuous functions. This leads to noncommutative geometry, where one considers noncommutative C\*-algebras as representing algebras of functions on a noncommutative space.
## Academic humour {#academic_humour}
- Hausdorff condition is illustrated by the pun that in Hausdorff spaces any two points can be \"housed off\" from each other by open sets.
- In the Mathematics Institute of the University of Bonn, in which Felix Hausdorff researched and lectured, there is a certain room designated the **Hausdorff-Raum**. This is a pun, as *Raum* means both *room* and *space* in German
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# Hermann Ebbinghaus
**Hermann Ebbinghaus** (24 January 1850 -- 26 February 1909) was a German psychologist who pioneered the experimental study of memory. Ebbinghaus discovered the forgetting curve and the spacing effect. He was the first person to describe the learning curve. He was the father of the neo-Kantian philosopher Julius Ebbinghaus.
## Early life {#early_life}
Ebbinghaus was born in Barmen, in the Rhine Province of the Kingdom of Prussia, as the son of a wealthy merchant, Carl Ebbinghaus. Little is known about his infancy except that he was brought up in the Lutheran faith and was a pupil at the town Gymnasium. At the age of 17 (1867), he began attending the University of Bonn, where he had planned to study history and philology. However, during his time there he developed an interest in philosophy. In 1870, his studies were interrupted when he served with the Prussian Army in the Franco-Prussian War. Following this short stint in the military, Ebbinghaus finished his dissertation on Eduard von Hartmann\'s **Philosophie des Unbewussten** (philosophy of the unconscious) and received his doctorate on 16 August 1873, when he was 23 years old. During the next three years, he spent time at Halle and Berlin.
## Professional career {#professional_career}
After acquiring his PhD, Ebbinghaus moved around England and France, tutoring students to support himself. In England, he may have taught in two small schools in the south of the country (Gorfein, 1885). In London, in a used bookstore, he came across Gustav Fechner\'s book *Elemente der Psychophysik* (*Elements of Psychophysics*), which spurred him to conduct memory experiments. After beginning his studies at the University of Berlin, he founded the third psychological testing lab in Germany (third to Wilhelm Wundt and Georg Elias Müller). He began his memory studies here in 1879. In 1885 --- the same year that he published his monumental work, *Über das Gedächtnis. Untersuchungen zur experimentellen Psychologie*, later published in English under the title *Memory: A Contribution to Experimental Psychology* --- he was made a professor at the University of Berlin, most likely in recognition of this publication. In 1890, along with Arthur König, he founded the psychological journal *Zeitschrift für Physiologie und Psychologie der Sinnesorgane* (\"The Psychology and Physiology of the Sense Organs\'\").
In 1894, he was passed over for promotion to head of the philosophy department at Berlin, most likely due to his lack of publications. Instead, Carl Stumpf received the promotion. As a result of this, Ebbinghaus left to join the University of Breslau (now Wrocław, Poland), in a chair left open by Theodor Lipps (who took over Stumpf\'s position when he moved to Berlin). While in Breslau, he worked on a commission that studied how children\'s mental ability declined during the school day. While the specifics on how these mental abilities were measured have been lost, the successes achieved by the commission laid the groundwork for future intelligence testing. At Breslau, he again founded a psychological testing laboratory.
In 1902, Ebbinghaus published his next piece of writing entitled *Die Grundzüge der Psychologie* (*Fundamentals of Psychology*). It was an instant success and continued to be long after his death. In 1904, he moved to Halle where he spent the last few years of his life. His last published work, *Abriss der Psychologie* (*Outline of Psychology*) was published six years later, in 1908. This, too, continued to be a success, being re-released in eight different editions. Shortly after this publication, on 26 February 1909, Ebbinghaus died from pneumonia at the age of 59.
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# Hermann Ebbinghaus
## Research on memory {#research_on_memory}
Ebbinghaus was determined to show that higher mental processes could actually be studied using experimentation, which was in opposition to the popularly held thought of the time. To control for most potentially confounding variables, Ebbinghaus wanted to use simple acoustic encoding and maintenance rehearsal for which a list of words could have been used. As learning would be affected by prior knowledge and understanding, he needed something that could be easily memorized but which had no prior cognitive associations. Easily formable associations with regular words would interfere with his results, so he used items that would later be called \"nonsense syllables\" (also known as the CVC trigram). A nonsense syllable is a consonant-vowel-consonant combination, where the consonant does not repeat and the syllable does not have prior meaning. BOL (sounds like \"Ball\") and DOT (already a word) would then not be allowed. However, syllables such as DAX, BOK, and YAT would all be acceptable (though Ebbinghaus left no examples). After eliminating the meaning-laden syllables, Ebbinghaus ended up with 2,300 resultant syllables. Once he had created his collection of syllables, he would pull out a number of random syllables from a box and then write them down in a notebook. Then, to the regular sound of a metronome, and with the same voice inflection, he would read out the syllables, and attempt to recall them at the end of the procedure. One investigation alone required 15,000 recitations. It was later determined that humans impose meaning even on nonsense syllables to make them more meaningful. The nonsense syllable PED (which is the first three letters of the word \"pedal\") turns out to be less nonsensical than a syllable such as KOJ; the syllables are said to differ in association value. It appears that Ebbinghaus recognized this, and only referred to the strings of syllables as \"nonsense\" in that the syllables might be less likely to have a specific meaning and he should make no attempt to make associations with them for easier retrieval.
### Limitations
There are several limitations to his work on memory. The most important one was that Ebbinghaus was the only subject in his study. This limited the study\'s generalizability to the population. Although he attempted to regulate his daily routine to maintain more control over his results, his decision to avoid the use of participants sacrificed the external validity of the study despite sound internal validity. In addition, although he tried to account for his personal influences, there is an inherent bias when someone serves as researcher as well as participant. Also, Ebbinghaus\'s memory research halted research in other, more complex matters of memory such as semantic and procedural memory and mnemonics.
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# Hermann Ebbinghaus
## Research on memory {#research_on_memory}
### Contributions
In 1885, he published his groundbreaking *Über das Gedächtnis* (\"On Memory\", later translated to English as *Memory. A Contribution to Experimental Psychology*) in which he described experiments he conducted on himself to describe the processes of learning and forgetting.
Ebbinghaus made several findings that are still relevant and supported to this day`{{when|date=June 2024}}`{=mediawiki}. First, Ebbinghaus made a set of 2,300 three letter syllables to measure mental associations that helped him find that memory is orderly. Second, and arguably his most famous finding, was the forgetting curve. The forgetting curve describes the exponential loss of information that one has learned. The sharpest decline occurs in the first twenty minutes and the decay is significant through the first hour. The curve levels off after about one day.
The learning curve described by Ebbinghaus refers to how fast one learns information. The sharpest increase occurs after the first try and then gradually evens out, meaning that less and less new information is retained after each repetition. Like the forgetting curve, the learning curve is exponential. Ebbinghaus had also documented the serial position effect, which describes how the position of an item affects recall. The two main concepts in the serial position effect are recency and primacy. The recency effect describes the increased recall of the most recent information because it is still in the short-term memory. The primacy effect causes better memory of the first items in a list due to increased rehearsal and commitment to long-term memory.
Another important discovery is that of savings. This refers to the amount of information retained in the subconscious even after this information cannot be consciously accessed. Ebbinghaus would memorize a list of items until perfect recall and then would not access the list until he could no longer recall any of its items.`{{clarify|date=June 2024|reason=If he stopped accessing the list, then he wouldn't know if he could still recall any items, since recalling an item accesses it, as mentioned in the previous sentence.}}`{=mediawiki} He then would relearn the list, and compare the new learning curve to the learning curve of his previous memorization of the list. The second list was generally memorized faster, and this difference between the two learning curves is what Ebbinghaus called \"savings\". Ebbinghaus also described the difference between involuntary and voluntary memory, the former occurring \"with apparent spontaneity and without any act of the will\" and the latter being brought \"into consciousness by an exertion of the will\".
Prior to Ebbinghaus, most contributions to the study of memory were undertaken by philosophers and centered on observational description and speculation. For example, Immanuel Kant simply described recognition and its components. On the other hand,Sir Francis Bacon claimed that the simple observation of the rote recollection of a previously learned list wasn\'t useful to understanding memory. This dichotomy between descriptive and experimental study of memory would resonate later in Ebbinghaus\'s life, particularly in his public argument with former colleague Wilhelm Dilthey. However, more than a century before Ebbinghaus, Johann Andreas Segner invented the \"Segner-wheel\" and would use both by seeing how fast a wheel with a hot coal attached had to move for the red ember circle from the coal to appear complete (see iconic memory). He proceeded to view the length of the after images.
Ebbinghaus\'s effect on memory research was almost immediate. With very few works published on memory in the previous two millennia, Ebbinghaus\'s works spurred memory research in the United States in the 1890s, with 32 papers published in 1894 alone. This research was coupled with the growing development of mechanized mnemometers (an outdated mechanical device used for presenting a series of stimuli to be memorized).
The reaction to his work in his day was mostly positive. Psychologist William James called the studies \"heroic\" and said that they were \"the single most brilliant investigation in the history of psychology\". Edward B. Titchener also mentioned that the studies were the greatest undertaking in the topic of memory since Aristotle.
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# Hermann Ebbinghaus
## Research on cramming {#research_on_cramming}
Ebbinghaus is the first person to compare distributed learning to cramming and one of the first people to carry out research on cramming.
## Sentence completion, illusion and research report standardization {#sentence_completion_illusion_and_research_report_standardization}
Ebbinghaus pioneered sentence completion exercises, which he developed in studying the abilities of schoolchildren. Alfred Binet borrowed and incorporated them into the Binet-Simon intelligence scale. Sentence completion was used extensively in memory research, especially in measuring implicit memory, and in psychotherapy to help find patients\' motivations. He influenced Charlotte Bühler, who studied language meaning and society.
Ebbinghaus discovered an optical illusion now known as the Ebbinghaus illusion, based on relative size perception. Despite the large amount of research done on this and similar illusions, little is known about why it occurs, but many speculate. During the illusion, two circles of identical size are placed near each other. One is surrounded by large circles while the other is surrounded by small circles, making the first appear smaller. Factors such as the different illustrations around the circles are called inducers and targets. Many theorists and scholars believe one of the main reasons for the illusions occurring are the geometrical features surrounding the spheres. This illusion is now used extensively in cognitive psychology research, to help map perception pathways in the human brain.
Ebbinghaus drafted the first standard research report. He arranged his paper on memory into four sections: the introduction, the methods, the results, and the discussion. The clear organization of this format so impressed his contemporaries that it became standard in the discipline.
## Discourse on the nature of psychology {#discourse_on_the_nature_of_psychology}
In addition to pioneering experimental psychology, Ebbinghaus was also a strong defender of this direction of the new science, as is illustrated by his public dispute with University of Berlin colleague, Wilhelm Dilthey. Shortly after Ebbinghaus left Berlin in 1893, Dilthey published a paper extolling the virtues of descriptive psychology, and condemning experimental psychology as boring, claiming that the mind was too complex, and that introspection was the desired method of studying the mind. The debate at the time had been primarily whether psychology should aim to explain or understand the mind and whether it belonged to the natural or human sciences. Many had seen Dilthey\'s work as an outright attack on experimental psychology, Ebbinghaus included, and he responded to Dilthey with a personal letter and also a long scathing public article. Amongst his counterarguments against Dilthey he mentioned that it is inevitable for psychology to do hypothetical work and that the kind of psychology that Dilthey was attacking was the one that existed before Ebbinghaus\'s \"experimental revolution\". Charlotte Bühler echoed his words some forty years later, stating that people like Ebbinghaus \"buried the old psychology in the 1890s\". Ebbinghaus explained his scathing review by saying that he could not believe that Dilthey was advocating the status quo of structuralists like Wilhelm Wundt and Titchener and attempting to stifle psychology\'s progress.
## Influences
There has been some speculation as to what influenced Ebbinghaus in his undertakings. None of his professors seem to have influenced him, nor are there suggestions that his colleagues affected him. Von Hartmann\'s work, on which Ebbinghaus based his doctorate, did suggest that higher mental processes were hidden from view, which may have spurred Ebbinghaus to attempt to prove otherwise. The one influence that has always been cited as having inspired Ebbinghaus was Gustav Fechner\'s two-volume *Elemente der Psychophysik.* (\"Elements of Psychophysics\", 1860), a book which he purchased second-hand in England. It is said that the meticulous mathematical procedures impressed Ebbinghaus so much that he wanted to do for psychology what Fechner had done for psychophysics. This inspiration is also evident in that Ebbinghaus dedicated his second work *Principles of Psychology* to Fechner, signing it \"I owe everything to you.\"
## Selected publications {#selected_publications}
- Ebbinghaus, H. (1885). *[Memory: A contribution to experimental psychology](https://web.archive.org/web/20050504104838/http://psy.ed.asu.edu/~classics/Ebbinghaus/index.htm).* New York: Dover.
- Ebbinghaus, H. (1902). *Grundzüge der Psychologie*. Leipzig: Veit & Co.
- Ebbinghaus, H. (1908). *[Psychology: An elementary textbook.](https://archive.org/details/cu31924029211286)* New York: Arno Press
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# Heat engine
thumb\|upright=1.0\|Figure 1: Heat engine diagram `{{Use dmy dates|date=April 2022}}`{=mediawiki} `{{Thermodynamics sidebar|cTopic=[[Thermodynamic system|Systems]]}}`{=mediawiki}
A **heat engine** is a system that transfers thermal energy to do mechanical or electrical work. While originally conceived in the context of mechanical energy, the concept of the heat engine has been applied to various other kinds of energy, particularly electrical, since at least the late 19th century. The heat engine does this by bringing a working substance from a higher state temperature to a lower state temperature. A heat source generates thermal energy that brings the working substance to the higher temperature state. The working substance generates work in the working body of the engine while transferring heat to the colder sink until it reaches a lower temperature state. During this process some of the thermal energy is converted into work by exploiting the properties of the working substance. The working substance can be any system with a non-zero heat capacity, but it usually is a gas or liquid. During this process, some heat is normally lost to the surroundings and is not converted to work. Also, some energy is unusable because of friction and drag.
In general, an engine is any machine that converts energy to mechanical work. Heat engines distinguish themselves from other types of engines by the fact that their efficiency is fundamentally limited by Carnot\'s theorem of thermodynamics. Although this efficiency limitation can be a drawback, an advantage of heat engines is that most forms of energy can be easily converted to heat by processes like exothermic reactions (such as combustion), nuclear fission, absorption of light or energetic particles, friction, dissipation and resistance. Since the heat source that supplies thermal energy to the engine can thus be powered by virtually any kind of energy, heat engines cover a wide range of applications.
Heat engines are often confused with the cycles they attempt to implement. Typically, the term \"engine\" is used for a physical device and \"cycle\" for the models.
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# Heat engine
## Overview
In thermodynamics, heat engines are often modeled using a standard engineering model such as the Otto cycle. The theoretical model can be refined and augmented with actual data from an operating engine, using tools such as an indicator diagram. Since very few actual implementations of heat engines exactly match their underlying thermodynamic cycles, one could say that a thermodynamic cycle is an ideal case of a mechanical engine. In any case, fully understanding an engine and its efficiency requires a good understanding of the (possibly simplified or idealised) theoretical model, the practical nuances of an actual mechanical engine and the discrepancies between the two.
In general terms, the larger the difference in temperature between the hot source and the cold sink, the larger is the potential thermal efficiency of the cycle. On Earth, the cold side of any heat engine is limited to being close to the ambient temperature of the environment, or not much lower than 300 kelvin, so most efforts to improve the thermodynamic efficiencies of various heat engines focus on increasing the temperature of the source, within material limits. The maximum theoretical efficiency of a heat engine (which no engine ever attains) is equal to the temperature difference between the hot and cold ends divided by the temperature at the hot end, each expressed in absolute temperature.
The efficiency of various heat engines proposed or used today has a large range:
- 3% (97 percent waste heat using low quality heat) for the ocean thermal energy conversion (OTEC) ocean power proposal
- 25% for most automotive gasoline engines
- 49% for a supercritical coal-fired power station such as the Avedøre Power Station
- 50%+ for long stroke marine Diesel engines [1](https://www.mhi.co.jp/technology/review/pdf/e451/e451021.pdf)
- 60% for a combined cycle gas turbine
The efficiency of these processes is roughly proportional to the temperature drop across them. Significant energy may be consumed by auxiliary equipment, such as pumps, which effectively reduces efficiency.
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# Heat engine
## Examples
Although some cycles have a typical combustion location (internal or external), they can often be implemented with the other. For example, John Ericsson developed an external heated engine running on a cycle very much like the earlier Diesel cycle. In addition, externally heated engines can often be implemented in open or closed cycles. In a closed cycle the working fluid is retained within the engine at the completion of the cycle whereas is an open cycle the working fluid is either exchanged with the environment together with the products of combustion in the case of the internal combustion engine or simply vented to the environment in the case of external combustion engines like steam engines and turbines.
### Everyday examples {#everyday_examples}
Everyday examples of heat engines include the thermal power station, internal combustion engine, firearms, refrigerators and heat pumps. Power stations are examples of heat engines run in a forward direction in which heat flows from a hot reservoir and flows into a cool reservoir to produce work as the desired product. Refrigerators, air conditioners and heat pumps are examples of heat engines that are run in reverse, i.e. they use work to take heat energy at a low temperature and raise its temperature in a more efficient way than the simple conversion of work into heat (either through friction or electrical resistance). Refrigerators remove heat from within a thermally sealed chamber at low temperature and vent waste heat at a higher temperature to the environment and heat pumps take heat from the low temperature environment and \'vent\' it into a thermally sealed chamber (a house) at higher temperature.
In general heat engines exploit the thermal properties associated with the expansion and compression of gases according to the gas laws or the properties associated with phase changes between gas and liquid states.
### Earth\'s heat engine {#earths_heat_engine}
Earth\'s atmosphere and hydrosphere---Earth\'s heat engine---are coupled processes that constantly even out solar heating imbalances through evaporation of surface water, convection, rainfall, winds and ocean circulation, when distributing heat around the globe.
A Hadley cell is an example of a heat engine. It involves the rising of warm and moist air in the earth\'s equatorial region and the descent of colder air in the subtropics creating a thermally driven direct circulation, with consequent net production of kinetic energy.
### Phase-change cycles {#phase_change_cycles}
In phase change cycles and engines, the working fluids are gases and liquids. The engine converts the working fluid from a gas to a liquid, from liquid to gas, or both, generating work from the fluid expansion or compression.
- Rankine cycle (classical steam engine)
- Regenerative cycle (steam engine more efficient than Rankine cycle)
- Organic Rankine cycle (Coolant changing phase in temperature ranges of ice and hot liquid water)
- Vapor to liquid cycle (drinking bird, injector, Minto wheel)
- Liquid to solid cycle (frost heaving -- water changing from ice to liquid and back again can lift rock up to 60 cm.)
- Solid to gas cycle (firearms -- solid propellants combust to hot gases.)
### Gas-only cycles {#gas_only_cycles}
In these cycles and engines the working fluid is always a gas (i.e., there is no phase change):
- Carnot cycle (Carnot heat engine)
- Ericsson cycle (Caloric Ship John Ericsson)
- Stirling cycle (Stirling engine, thermoacoustic devices)
- Internal combustion engine (ICE):
- Otto cycle (e.g. gasoline/petrol engine)
- Diesel cycle (e.g. Diesel engine)
- Atkinson cycle (Atkinson engine)
- Brayton cycle or Joule cycle originally Ericsson cycle (gas turbine)
- Lenoir cycle (e.g., pulse jet engine)
- Miller cycle (Miller engine)
### Liquid-only cycles {#liquid_only_cycles}
In these cycles and engines the working fluid are always like liquid:
- Stirling cycle (Malone engine)
### Electron cycles {#electron_cycles}
- Johnson thermoelectric energy converter
- Thermoelectric (Peltier--Seebeck effect)
- Thermogalvanic cell
- Thermionic emission
- Thermotunnel cooling
### Magnetic cycles {#magnetic_cycles}
- Thermo-magnetic motor (Tesla)
### Cycles used for refrigeration {#cycles_used_for_refrigeration}
A domestic refrigerator is an example of a heat pump: a heat engine in reverse. Work is used to create a heat differential. Many cycles can run in reverse to move heat from the cold side to the hot side, making the cold side cooler and the hot side hotter. Internal combustion engine versions of these cycles are, by their nature, not reversible.
Refrigeration cycles include:
- Air cycle machine
- Gas-absorption refrigerator
- Magnetic refrigeration
- Stirling cryocooler
- Vapor-compression refrigeration
- Vuilleumier cycle
### Evaporative heat engines {#evaporative_heat_engines}
The Barton evaporation engine is a heat engine based on a cycle producing power and cooled moist air from the evaporation of water into hot dry air.
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# Heat engine
## Examples
### Mesoscopic heat engines {#mesoscopic_heat_engines}
Mesoscopic heat engines are nanoscale devices that may serve the goal of processing heat fluxes and perform useful work at small scales. Potential applications include e.g. electric cooling devices. In such mesoscopic heat engines, work per cycle of operation fluctuates due to thermal noise. There is exact equality that relates average of exponents of work performed by any heat engine and the heat transfer from the hotter heat bath. This relation transforms the Carnot\'s inequality into exact equality. This relation is also a Carnot cycle equality
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# Heat engine
## Efficiency
The efficiency of a heat engine relates how much useful work is output for a given amount of heat energy input.
From the laws of thermodynamics, after a completed cycle:
$$W + Q = \Delta_{cycle}U = 0$$
: and therefore
: $W = -Q = - (Q_c + Q_h)$
: where
: $W = -\oint PdV$ is the net work extracted from the engine in one cycle. (It is negative, in the IUPAC convention, since work is *done by* the engine.)
: $Q_h > 0$ is the heat energy taken from the high temperature heat source in the surroundings in one cycle. (It is positive since heat energy is *added* to the engine.)
: $Q_c = -|Q_c|<0$ is the waste heat given off by the engine to the cold temperature heat sink. (It is negative since heat is *lost* by the engine to the sink.)
In other words, a heat engine absorbs heat energy from the high temperature heat source, converting part of it to useful work and giving off the rest as waste heat to the cold temperature heat sink.
In general, the efficiency of a given heat transfer process is defined by the ratio of \"what is taken out\" to \"what is put in\". (For a refrigerator or heat pump, which can be considered as a heat engine run in reverse, this is the coefficient of performance and it is ≥ 1.) In the case of an engine, one desires to extract work and has to put in heat $Q_h$, for instance from combustion of a fuel, so the engine efficiency is reasonably defined as
$$\eta = \frac{|W|}{Q_h} = \frac{Q_h + Q_c}{Q_h} = 1 + \frac{Q_c}{Q_h} = 1 - \frac{|Q_c|}{Q_h}$$
The efficiency is less than 100% because of the waste heat $Q_c<0$ unavoidably lost to the cold sink (and corresponding compression work put in) during the required recompression at the cold temperature before the power stroke of the engine can occur again.
The *theoretical* maximum efficiency of any heat engine depends only on the temperatures it operates between. This efficiency is usually derived using an ideal imaginary heat engine such as the Carnot heat engine, although other engines using different cycles can also attain maximum efficiency. Mathematically, after a full cycle, the overall change of entropy is zero:
$\ \ \ \Delta S_h + \Delta S_c = \Delta_{cycle} S = 0$
Note that $\Delta S_h$ is positive because isothermal expansion in the power stroke increases the multiplicity of the working fluid while $\Delta S_c$ is negative since recompression decreases the multiplicity. If the engine is ideal and runs reversibly, $Q_h = T_h\Delta S_h$ and $Q_c = T_c\Delta S_c$, and thus
$Q_h / T_h + Q_c / T_c = 0$,
which gives $Q_c /Q_h = -T_c / T_h$ and thus the Carnot limit for heat-engine efficiency,
$$\eta_\text{max} = 1 - \frac{T_c}{T_h}$$
where $T_h$ is the absolute temperature of the hot source and $T_c$ that of the cold sink, usually measured in kelvins.
The reasoning behind this being the **maximal** efficiency goes as follows. It is first assumed that if a more efficient heat engine than a Carnot engine is possible, then it could be driven in reverse as a heat pump. Mathematical analysis can be used to show that this assumed combination would result in a net decrease in entropy. Since, by the second law of thermodynamics, this is statistically improbable to the point of exclusion, the Carnot efficiency is a theoretical upper bound on the reliable efficiency of *any* thermodynamic cycle.
Empirically, no heat engine has ever been shown to run at a greater efficiency than a Carnot cycle heat engine.
Figure 2 and Figure 3 show variations on Carnot cycle efficiency with temperature. Figure 2 indicates how efficiency changes with an increase in the heat addition temperature for a constant compressor inlet temperature. Figure 3 indicates how the efficiency changes with an increase in the heat rejection temperature for a constant turbine inlet temperature.
-- --
-- --
### Endo-reversible heat-engines {#endo_reversible_heat_engines}
By its nature, any maximally efficient Carnot cycle must operate at an infinitesimal temperature gradient; this is because any transfer of heat between two bodies of differing temperatures is irreversible, therefore the Carnot efficiency expression applies only to the infinitesimal limit. The major problem is that the objective of most heat-engines is to output power, and infinitesimal power is seldom desired.
A different measure of ideal heat-engine efficiency is given by considerations of endoreversible thermodynamics, where the system is broken into reversible subsystems, but with non reversible interactions between them. A classical example is the Curzon--Ahlborn engine, very similar to a Carnot engine, but where the thermal reservoirs at temperature $T_h$ and $T_c$ are allowed to be different from the temperatures of the substance going through the reversible Carnot cycle: $T'_h$ and $T'_c$. The heat transfers between the reservoirs and the substance are considered as conductive (and irreversible) in the form $dQ_{h,c}/dt = \alpha (T_{h,c}-T'_{h,c})$. In this case, a tradeoff has to be made between power output and efficiency. If the engine is operated very slowly, the heat flux is low, $T\approx T'$ and the classical Carnot result is found
$$\eta = 1 - \frac{T_c}{T_h}$$, but at the price of a vanishing power output. If instead one chooses to operate the engine at its maximum output power, the efficiency becomes
$$\eta = 1 - \sqrt{\frac{T_c}{T_h}}$$ (Note: *T* in units of K or °R)
This model does a better job of predicting how well real-world heat-engines can do (Callen 1985, see also endoreversible thermodynamics):
*Power station* $T_c$ (°C) $T_h$ (°C) $\eta$ (Carnot) $\eta$ (Endoreversible) $\eta$ (Observed)
--------------------------------------------- ------------ ------------ ----------------- ------------------------- -------------------
West Thurrock (UK) coal-fired power station 25 565 0.64 0.40 0.36
CANDU (Canada) nuclear power station 25 300 0.48 0.28 0.30
Larderello (Italy) geothermal power station 80 250 0.33 0.178 0.16
: **Efficiencies of power stations**
As shown, the Curzon--Ahlborn efficiency much more closely models that observed.
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# Heat engine
## History
Heat engines have been known since antiquity but were only made into useful devices at the time of the industrial revolution in the 18th century. They continue to be developed today.
## Enhancements
Engineers have studied the various heat-engine cycles to improve the amount of usable work they could extract from a given power source. The Carnot cycle limit cannot be reached with any gas-based cycle, but engineers have found at least two ways to bypass that limit and one way to get better efficiency without bending any rules:
1. Increase the temperature difference in the heat engine. The simplest way to do this is to increase the hot side temperature, which is the approach used in modern combined-cycle gas turbines. Unfortunately, physical limits (such as the melting point of the materials used to build the engine) and environmental concerns regarding NO~x~ production (if the heat source is combustion with ambient air) restrict the maximum temperature on workable heat-engines. Modern gas turbines run at temperatures as high as possible within the range of temperatures necessary to maintain acceptable NO~x~ output . Another way of increasing efficiency is to lower the output temperature. One new method of doing so is to use mixed chemical working fluids, then exploit the changing behavior of the mixtures. One of the most famous is the so-called Kalina cycle, which uses a 70/30 mix of ammonia and water as its working fluid. This mixture allows the cycle to generate useful power at considerably lower temperatures than most other processes.
2. Exploit the physical properties of the working fluid. The most common such exploitation is the use of water above the critical point (supercritical water). The behavior of fluids above their critical point changes radically, and with materials such as water and carbon dioxide it is possible to exploit those changes in behavior to extract greater thermodynamic efficiency from the heat engine, even if it is using a fairly conventional Brayton or Rankine cycle. A newer and very promising material for such applications is supercritical CO~2~. SO~2~ and xenon have also been considered for such applications. Downsides include issues of corrosion and erosion, the different chemical behavior above and below the critical point, the needed high pressures and -- in the case of sulfur dioxide and to a lesser extent carbon dioxide -- toxicity. Among the mentioned compounds xenon is least suitable for use in a nuclear reactor due to the high neutron absorption cross section of almost all isotopes of xenon, whereas carbon dioxide and water can also double as a neutron moderator for a thermal spectrum reactor.
3. Exploit the chemical properties of the working fluid. A fairly new and novel exploit is to use exotic working fluids with advantageous chemical properties. One such is nitrogen dioxide (NO~2~), a toxic component of smog, which has a natural dimer as di-nitrogen tetraoxide (N~2~O~4~). At low temperature, the N~2~O~4~ is compressed and then heated. The increasing temperature causes each N~2~O~4~ to break apart into two NO~2~ molecules. This lowers the molecular weight of the working fluid, which drastically increases the efficiency of the cycle. Once the NO~2~ has expanded through the turbine, it is cooled by the heat sink, which makes it recombine into N~2~O~4~. This is then fed back by the compressor for another cycle. Such species as aluminium bromide (Al~2~Br~6~), NOCl, and Ga~2~I~6~ have all been investigated for such uses. To date, their drawbacks have not warranted their use, despite the efficiency gains that can be realized
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# Heimdall
In Norse mythology, **Heimdall** (from Old Norse **Heimdallr**; modern Icelandic **Heimdallur**) is a god. He is the son of Odin and nine mothers. Heimdall keeps watch for invaders and the onset of Ragnarök from his dwelling Himinbjörg, where the burning rainbow bridge Bifröst meets the sky. He is attested as possessing foreknowledge and keen senses, particularly eyesight and hearing. The god and his possessions are described in enigmatic manners. For example, Heimdall is golden-toothed, \"the head is called his sword,\" and he is \"the whitest of the gods.\"
Heimdall possesses the resounding horn Gjallarhorn and the golden-maned horse Gulltoppr, along with a store of mead at his dwelling. He is the son of Nine Mothers, and he is said to be the originator of social classes among humanity. Other notable stories include the recovery of Freyja\'s treasured possession Brísingamen while doing battle in the shape of a seal with Loki. The antagonistic relationship between Heimdall and Loki is notable, as they are foretold to kill one another during the events of Ragnarök. Heimdallr is also known as **Rig**, **Hallinskiði**, **Gullintanni**, and **Vindlér** or **Vindhlér**.
Heimdall is attested in the *Poetic Edda*, compiled in the 13th century from earlier traditional material; in the *Prose Edda* and *Heimskringla*, both written in the 13th century; in the poetry of skalds; and likely in a runic inscription on the Saltfleetby spindle-whorl found in England. Two lines of an otherwise lost poem about the god, *Heimdalargaldr*, survive. Due to the enigmatic nature of these attestations, scholars have produced various theories about the nature of the god, including his relation to sheep, borders, and waves.
## Names and etymology {#names_and_etymology}
The etymology of the name is obscure, but \'the one who illuminates the world\' has been proposed. *Heimdallr* may be connected to *Mardöll*, one of Freyja\'s names. *Heimdallr* and its variants are usually anglicized as *Heimdall* (`{{IPAc-en|ˈ|h|eɪ|m|d|ɑː|l}}`{=mediawiki}; with the nominative *-r* dropped).
Heimdall is attested as having three other names; *Hallinskiði*, *Gullintanni*, and *Vindlér* or *Vindhlér*. The name *Hallinskiði* is obscure, but has resulted in a series of attempts at deciphering it. *Gullintanni* literally means \'the one with the golden teeth\'. *Vindlér* (or *Vindhlér*) translates as either \'the one protecting against the wind\' or \'wind-sea\'. All three have resulted in numerous theories about the god.
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# Heimdall
## Attestations
### Saltfleetby spindle-whorl inscription {#saltfleetby_spindle_whorl_inscription}
Heimdallr is likely mentioned on the Saltfleetby spindle-whorl, a lead spindle whorl bearing an Old Norse Younger Fuþark inscription that was discovered in Saltfleetby in eastern England in 2010. The spindle-whorl itself is dated from the 10th to 12th centuries CE, with the writing possibly being added significantly after the object was made. Whilst there are difficulties in interpreting the inscription, it likely records a charm asking for help from Odin, Heimdallr and *Þalfa*, a figure whose name closely resembles that of Þjálfi, one of Thor\'s servants. The religion of the writer is debated, with the invoking of Germanic gods not procluding adherence to Christianity, but also possibly attesting to the continuing of Old Nordic religion in some English communities significantly after the establishment of Christianity in the region.
### *Poetic Edda* {#poetic_edda}
In the *Poetic Edda*, Heimdall is attested in six poems; *Völuspá*, *Grímnismál*, *Lokasenna*, *Þrymskviða*, *Rígsþula*, and *Hrafnagaldr Óðins*.
Heimdall is mentioned three times in *Völuspá*. In the first stanza of the poem, the undead völva reciting the poem calls out for listeners to be silent and refers to the Norse god:
> +------------------------------------------------------+-----------------------------------------------+---+
> | Benjamin Thorpe translation: | Henry Adams Bellows translation: | |
> | | | |
> | : For silence I pray all sacred children, | : Hearing I ask from the holy races, | |
> | : great and small, sons of Heimdall. | : From Heimdall\'s sons, both high and low; | |
> | : they will that I Valfather\'s deeds recount, | : Thou wilt, Valfather, that well I relate. | |
> | : men\'s ancient saws, those that I best remember. | : Old tales I remember of men long ago. | |
> +------------------------------------------------------+-----------------------------------------------+---+
This stanza has led to various scholarly interpretations. The \"holy races\" have been considered variously as either humanity or the gods. The notion of humanity as \"Heimdall\'s sons\" is otherwise unattested and has also resulted in various interpretations. Some scholars have pointed to the prose introduction to the poem *Rígsþula*, where Heimdall is said to have once gone about people, slept between couples, and so doled out classes among them (see *Rígsthula* section below).
Later in *Völuspá*, the völva foresees the events of Ragnarök and the role in which Heimdall and Gjallarhorn will play at its onset; Heimdall will raise his horn and blow loudly. Due to manuscript differences, translations of the stanza vary:
+-------------------------------------------------------+----------------------------------------------+---+
| Benjamin Thorpe translation: | Henry Adams Bellows translation: | |
| | | |
| : Mim\'s sons dance, | : Fast move the sons of Mim and fate | |
| : but the central tree takes fire, | : Is heard in the note of the Gjallarhorn; | |
| : at the resounding Giallar-horn. | : Loud blows Heimdall, the horn is aloft, | |
| : Loud blows Heimdall, | : In fear quake all who on Hel-roads are. | |
| : his horn is raised; Odin speaks with Mim\'s head. | | |
+-------------------------------------------------------+----------------------------------------------+---+
Regarding this stanza, scholar Andy Orchard comments that the name *Gjallarhorn* may here mean \"horn of the river Gjöll\" as \"Gjöll is the name of one of the rivers of the Underworld, whence much wisdom is held to derive\", but notes that in the poem *Grímnismál* Heimdall is said to drink fine mead in his heavenly home Himinbjörg.
Earlier in the same poem, the völva mentions a scenario involving the hearing or horn (depending on translation of the Old Norse noun *hljóð*---translations bolded below for the purpose of illustration) of the god Heimdall:
> +---------------------------------------------------+------------------------------------------------+------------------------------------------------------+
> | : Benjamin Thorpe translation: | : Henry Adams Bellows translation: | : Carolyne Larrington translation: |
> | : She knows that **Heimdall\'s horn** is hidden | : I know of the **horn of Heimdall**, hidden | : She knows that **Heimdall\'s hearing** is hidden |
> | : under the heaven-bright holy tree. | : Under the high-reaching holy tree; | : under the radiant, sacred tree; |
> | : A river she sees flow, with foamy fall, | : On it there pours from Valfather\'s pledge | : she sees, pouring down, the muddy torrent |
> | : from Valfather\'s pledge. | : A mighty stream: would you know yet more? | : from the wager of Father of the Slain; do you |
> | : Understand ye yet, or what? | | : understand yet, or what more? |
> +---------------------------------------------------+------------------------------------------------+------------------------------------------------------+
Scholar Paul Schach comments that the stanzas in this section of *Völuspá* are \"all very mysterious and obscure, as it was perhaps meant to be\". Schach details that \"*Heimdallar hljóð* has aroused much speculation. Snorri \[in the *Prose Edda*\] seems to have confused this word with *gjallarhorn*, but there is otherwise no attestation of the use of *hljóð* in the sense of \'horn\' in Icelandic. Various scholars have read this as \"hearing\" rather than \"horn\".
Scholar Carolyne Larrington comments that if \"hearing\" rather than \"horn\" is understood to appear in this stanza, the stanza indicates that Heimdall, like Odin, has left a body part in the well; his ear. Larrington says that \"Odin exchanged one of his eyes for wisdom from Mimir, guardian of the well, while Heimdall seems to have forfeited his ear.\"
In the poem *Grímnismál*, Odin (disguised as *Grímnir*), tortured, starved and thirsty, tells the young Agnar of a number of mythological locations. The eighth location he mentions is Himinbjörg, where he says that Heimdall drinks fine mead:
> +------------------------------------------------------+-------------------------------------------------------+---+
> | Benjamin Thorpe translation: | Henry Adams Bellows translation: | |
> | | | |
> | : Himinbiörg is the eighth, where Heimdall, | : Himingbjorg is the eighth, and Heimdall there | |
> | : it is said, rules o\'er the holy fanes: | : O\'er men holds sway, it is said; | |
> | : there the gods\' watchman, in his tranquil home, | : In his well-built house does the warder of heaven | |
> | : drinks joyful the good mead. | : The good mead gladly drink. | |
> +------------------------------------------------------+-------------------------------------------------------+---+
Regarding the above stanza, Henry Adams Bellows comments that \"in this stanza the two functions of Heimdall---as father of humanity \[ . . . \] and as warder of the gods---seem both to be mentioned, but the second line in the manuscripts is apparently in bad shape, and in the editions it is more or less conjecture\".
In the poem *Lokasenna*, Loki flyts with various gods who have met together to feast. At one point during the exchanges, the god Heimdall says that Loki is drunk and witless, and asks Loki why he won\'t stop speaking. Loki tells Heimdall to be silent, that he was fated a \"hateful life\", that Heimdall must always have a muddy back, and that he must serve as watchman of the gods. The goddess Skaði interjects and the flyting continues in turn.
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# Heimdall
## Attestations
### *Poetic Edda* {#poetic_edda}
The poem *Þrymskviða* tells of Thor\'s loss of his hammer, Mjöllnir, to the jötnar and quest to get it back. At one point in the tale, the gods gather at the thing and debate how to get Thor\'s hammer back from the jötnar, who demand the beautiful goddess Freyja in return for it. Heimdall advises that they simply dress Thor up as Freyja, during which he is described as *hvítastr ása* (translations of the phrase vary below) and is said to have foresight like the Vanir, a group of gods:
> +-----------------------------------------------+--------------------------------------------------+-----------------------------------------------------------+
> | Benjamin Thorpe translation: | Henry Adams Bellows translation: | Jeramy Dodds translation: |
> | | | |
> | : Then said Heimdall, of Æsir brightest--- | : Then Heimdall spake, whitest of the gods, | : The most glittering of gods, Heimdall, who, |
> | : he well foresaw, like other Vanir--- | : Like the Wanes he knew the future well: | : like the Vanir, is gifted with the gift of foresight, |
> | : Let us clothe Thor with bridal raiment, | : \"Bind we on Thor the bridal veil, | : said: \'Let\'s strap a bridal veil over Thor\'s face |
> | : let him have the famed Brîsinga necklace. | : Let him bear the mighty Brisings\' necklace; | : and let him don the Brising necklace. |
> | : \"Let by his side keys jingle, | : \"Keys around him let there rattle, | : \'Let the wedlock keys jingle around his waist, |
> | : and woman\'s weeds fall around his knees, | : And down to his knees hang woman\'s dress; | : and dress him in a woman\'s dress to his knees |
> | : but on his breast place precious stones, | : With gems full broad upon his breast, | : and loop giant gems across his chest |
> | : and a neat coif set on his head.\" | : And a pretty cap to crown his head.\" | : and top him off with a stylish headdress.\' |
> +-----------------------------------------------+--------------------------------------------------+-----------------------------------------------------------+
Regarding Heimdall\'s status as *hvítastr ása* (variously translated above as \"brightest\" (Thorpe), \"whitest\" (Bellows), and \"most glittering\" (Dodds)) and the comparison to the Vanir, scholar John Lindow comments that there are no other indications of Heimdall being considered among the Vanir (on Heimdall\'s status as \"*hvítastr ása*\", see \"scholarly reception\" below).
The introductory prose to the poem *Rígsþula* says that \"people say in the old stories\" that Heimdall, described as a god among the Æsir, once fared on a journey. Heimdall wandered along a seashore, and referred to himself as *Rígr*. In the poem, Rígr, who is described as a wise and powerful god, walks in the middle of roads on his way to steads, where he meets a variety of couples and dines with them, giving them advice and spending three nights at a time between them in their bed. The wives of the couples become pregnant, and from them come the various classes of humanity.
Eventually a warrior home produces a promising boy, and as the boy grows older, Rígr comes out of a thicket, teaches the boy runes, gives him a name, and proclaims him to be his son. Rígr tells him to strike out and get land for himself. The boy does so, and so becomes a great war leader with many estates. He marries a beautiful woman and the two have many children and are happy. One of the children eventually becomes so skilled that he is able to share in runic knowledge with Heimdall, and so earns the title of *Rígr* himself. The poem breaks off without further mention of the god.
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# Heimdall
## Attestations
### *Prose Edda* {#prose_edda}
In the *Prose Edda*, Heimdall is mentioned in the books *Gylfaginning*, *Skáldskaparmál*, and *Háttatal*. In *Gylfaginning*, the enthroned figure of High tells the disguised mythical king Gangleri of various gods, and, in chapter 25, mentions Heimdall. High says that Heimdall is known as \"the white As\", is \"great and holy\", and that nine maidens, all sisters, gave birth to him. Heimdall is called *Hallinskiði* and *Gullintanni*, and he has gold teeth. High continues that Heimdall lives in \"a place\" called Himinbjörg and that it is near Bifröst. Heimdall is the watchman of the gods, and he sits on the edge of heaven to guard the Bifröst bridge from the berg jötnar. Heimdall requires less sleep than a bird, can see at night just as well as if it were day, and for over a hundred leagues. Heimdall\'s hearing is also quite keen; he can hear grass as it grows on the earth, wool as it grows on sheep, and anything louder. Heimdall possesses a trumpet, Gjallarhorn, that, when blown, can be heard in all worlds, and \"the head is referred to as Heimdall\'s sword\". High then quotes the above-mentioned *Grímnismál* stanza about Himinbjörg and provides two lines from the otherwise lost poem about Heimdall, *Heimdalargaldr*, in which he proclaims himself to be the son of Nine Mothers.
In chapter 49, High tells of the god Baldr\'s funeral procession. Various deities are mentioned as having attended, including Heimdall, who there rode his horse Gulltopr.
In chapter 51, High foretells the events of Ragnarök. After the enemies of the gods will gather at the plain Vígríðr, Heimdall will stand and mightily blow into Gjallarhorn. The gods will awake and assemble together at the thing. At the end of the battle between various gods and their enemies, Heimdall will face Loki and they will kill one another. After, the world will be engulfed in flames. High then quotes the above-mentioned stanza regarding Heimdall raising his horn in *Völuspá*.
At the beginning of *Skáldskaparmál*, Heimdall is mentioned as having attended a banquet in Asgard with various other deities. Later in the book, *Húsdrápa*, a poem by 10th century skald Úlfr Uggason, is cited, during which Heimdall is described as having ridden to Baldr\'s funeral pyre.
In chapter 8, means of referring to Heimdall are provided; \"son of nine mothers\", \"guardian of the gods\", \"the white As\" (see *Poetic Edda* discussion regarding *hvítastr ása* above), \"Loki\'s enemy\", and \"recoverer of Freyja\'s necklace\". The section adds that the poem *Heimdalargaldr* is about him, and that, since the poem, \"the head has been called Heimdall\'s doom: man\'s doom is an expression for sword\". Hiemdallr is the owner of Gulltoppr, is also known as Vindhlér, and is a son of Odin. Heimdall visits Vágasker and Singasteinn and there vied with Loki for Brísingamen. According to the chapter, the skald Úlfr Uggason composed a large section of his *Húsdrápa* about these events and that *Húsdrápa* says that the two were in the shape of seals. A few chapters later, ways of referring to Loki are provided, including \"wrangler with Heimdall and Skadi\", and section of Úlfr Uggason\'s *Húsdrápa* is then provided in reference:
> Renowned defender \[Heimdall\] of the powers\' way \[Bifrost\], kind of counsel, competes with Farbauti\'s terribly sly son at Singastein. Son of eight mothers plus one, might of mood, is first to get hold of the beautiful sea-kidney \[jewel, Brisingamen\]. I announce it in strands of praise.
The chapter points out that in the above *Húsdrápa* section Heimdall is said to be the son of nine mothers.
Heimdall is mentioned once in *Háttatal*. There, in a composition by Snorri Sturluson, a sword is referred to as \"Vindhlér\'s helmet-filler\", meaning \"Heimdall\'s head\".
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# Heimdall
## Attestations
### *Heimskringla*
In *Ynglinga saga* compiled in *Heimskringla*, Snorri presents a euhemerized origin of the Norse gods and rulers descending from them. In chapter 5, Snorri asserts that the Æsir settled in what is now Sweden and built various temples. Snorri writes that Odin settled in Lake Logrin \"at a place which formerly was called Sigtúnir. There he erected a large temple and made sacrifices according to the custom of the Æsir. He took possession of the land as far as he had called it Sigtúnir. He gave dwelling places to the temple priests.\" Snorri adds that, after this, Njörðr dwelt in Nóatún, Freyr dwelt in Uppsala, Heimdall at Himinbjörg, Thor at Þrúðvangr, Baldr at Breiðablik and that to everyone Odin gave fine estates.
## Visual depictions {#visual_depictions}
A figure holding a large horn to his lips and clasping a sword on his hip appears on a stone cross from the Isle of Man. Some scholars have theorized that this figure is a depiction of Heimdall with Gjallarhorn.
A 9th or 10th century Gosforth Cross in Cumbria, England depicts a figure holding a horn and a sword standing defiantly before two open-mouthed beasts. This figure has been often theorized as depicting Heimdall with Gjallarhorn.
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# Heimdall
## Scholarly reception {#scholarly_reception}
Heimdall\'s attestations have proven troublesome and enigmatic to interpret for scholars. A variety of sources describe the god as born from Nine Mothers, a puzzling description (for more in-depth discussion, see Nine Mothers of Heimdallr). Various scholars have interpreted this as a reference to the Nine Daughters of Ægir and Rán, personifications of waves. This would therefore mean Heimdall is born from the waves, an example of a deity born from the sea.
In the textual corpus, Heimdall is frequently described as maintaining a particular association with boundaries, borders, and liminal spaces, both spatial and temporal. For example, *Gylfaginning* describes the god as guarding the border of the land of the gods, Heimdall meets humankind at a coast, and, if accepted as describing Heimdall, *Völuspá hin skamma* describes him as born \'at the edge of the world\' in \'days of yore\' by the Nine Daughters of Ægir and Rán, and it is Heimdall\'s horn that signals the transition to the events of Ragnarök.
Additionally, Heimdall has a particular association with male sheep, rams. A form of the deity\'s name, *Heimdali*, occurs twice as a name for \'ram\' in *Skáldskaparmál*, as does Heimdall\'s name *Hallinskíði*. Heimdall\'s unusual physical description has also been seen by various scholars as fitting this association: As mentioned above, Heimdall is described as gold-toothed (by way of his name *Gullintanni*), as having the ability to hear grass grow and the growth of wool on sheep, and as owning a sword called \'head\' (rams have horns on their heads). This may mean that Heimdall was associated with the ram perhaps as a sacred and/or sacrificial animal or that the ancient Scandinavians may have conceived of him as having been a ram in appearance.
All of these topics---Heimdall\'s birth, his association with borders and boundaries, and his connection to sheep---have led to significant discussion among scholars. For example, influential philologist and folklorist Georges Dumézil, comparing motifs and clusters of motifs in western Europe, proposes the following explanation for Heimdall\'s birth and association with rams (italics are Dumézil\'s own):
## In popular culture {#in_popular_culture}
As with many aspects of Norse mythology, Heimdall has appeared in many modern works. Heimdall appears as a character in Marvel Comics and is portrayed in the film versions by English actor Idris Elba.
Heimdall is the namesake of a crater on Callisto, a moon of Jupiter.
Heimdall is the protagonist of an eponymous video game released in 1991 and its 1994 sequel, *Heimdall 2*. In the 2002 Ensemble Studios game *Age of Mythology*, Heimdall is one of 12 gods the Norse can choose to worship. Heimdallr is one of the playable gods in the multiplayer online battle arena game *Smite*. Heimdall also appears as an antagonist in the 2022 action-adventure video game *God of War Ragnarök* and is played by the American actor Scott Porter
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# Homeomorphism
thumb\|upright=1.2\|An often-repeated mathematical joke is that topologists cannot tell the difference between a coffee mug and a donut, since a sufficiently pliable donut could be reshaped to the form of a coffee mug by creating a dimple and progressively enlarging it, while preserving the donut hole in the mug\'s handle. This illustrates that a coffee mug and a donut are homeomorphic.
In mathematics and more specifically in topology, a **homeomorphism** (from Greek roots meaning \"similar shape\", named by Henri Poincaré), also called **topological isomorphism**, or **bicontinuous function**, is a bijective and continuous function between topological spaces that has a continuous inverse function. Homeomorphisms are the isomorphisms in the category of topological spaces---that is, they are the mappings that preserve all the topological properties of a given space. Two spaces with a homeomorphism between them are called **homeomorphic**, and from a topological viewpoint they are the same.
Very roughly speaking, a topological space is a geometric object, and a homeomorphism results from a continuous deformation of the object into a new shape. Thus, a square and a circle are homeomorphic to each other, but a sphere and a torus are not. However, this description can be misleading. Some continuous deformations do not produce homeomorphisms, such as the deformation of a line into a point. Some homeomorphisms do not result from continuous deformations, such as the homeomorphism between a trefoil knot and a circle. Homotopy and isotopy are precise definitions for the informal concept of *continuous deformation*.
## Definition
A function $f : X \to Y$ between two topological spaces is a **homeomorphism** if it has the following properties:
- $f$ is a bijection (one-to-one and onto),
- $f$ is continuous,
- the inverse function $f^{-1}$ is continuous ($f$ is an open mapping).
A homeomorphism is sometimes called a *bicontinuous* function. If such a function exists, $X$ and $Y$ are **homeomorphic**. A **self-homeomorphism** is a homeomorphism from a topological space onto itself. Being \"homeomorphic\" is an equivalence relation on topological spaces. Its equivalence classes are called **homeomorphism classes**.
The third requirement, that $f^{-1}$ be continuous, is essential. Consider for instance the function $f : [0,2\pi) \to S^1$ (the unit circle in `{{tmath|\R^2}}`{=mediawiki}) defined by$f(\varphi) = (\cos\varphi,\sin\varphi).$ This function is bijective and continuous, but not a homeomorphism ($S^1$ is compact but $[0,2\pi)$ is not). The function $f^{-1}$ is not continuous at the point $(1,0),$ because although $f^{-1}$ maps $(1,0)$ to $0,$ any neighbourhood of this point also includes points that the function maps close to $2\pi,$ but the points it maps to numbers in between lie outside the neighbourhood.
Homeomorphisms are the isomorphisms in the category of topological spaces. As such, the composition of two homeomorphisms is again a homeomorphism, and the set of all self-homeomorphisms $X \to X$ forms a group, called the **homeomorphism group** of *X*, often denoted $\operatorname{Homeo}(X).$ This group can be given a topology, such as the compact-open topology, which under certain assumptions makes it a topological group.
In some contexts, there are homeomorphic objects that cannot be continuously deformed from one to the other. Homotopy and isotopy are equivalence relations that have been introduced for dealing with such situations.
Similarly, as usual in category theory, given two spaces that are homeomorphic, the space of homeomorphisms between them, $\operatorname{Homeo}(X,Y),$ is a torsor for the homeomorphism groups $\operatorname{Homeo}(X)$ and $\operatorname{Homeo}(Y),$ and, given a specific homeomorphism between $X$ and $Y,$ all three sets are identified.`{{clarify|reason=Which?|date=July 2023}}`{=mediawiki}
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# Homeomorphism
## Examples
thumb\|upright=1.15\|A thickened trefoil knot is homeomorphic to a solid torus, but not isotopic in `{{tmath|\R^3.}}`{=mediawiki} Continuous mappings are not always realizable as deformations.
- The open interval $(a,b)$ is homeomorphic to the real numbers `{{tmath|\R}}`{=mediawiki} for any $a < b.$ (In this case, a bicontinuous forward mapping is given by $f(x) = \frac{1}{a-x} + \frac{1}{b-x}$ while other such mappings are given by scaled and translated versions of the `{{math|tan}}`{=mediawiki} or `{{math|arg tanh}}`{=mediawiki} functions).
- The unit 2-disc $D^2$ and the unit square in `{{tmath|\R^2}}`{=mediawiki} are homeomorphic; since the unit disc can be deformed into the unit square. An example of a bicontinuous mapping from the square to the disc is, in polar coordinates, $(\rho, \theta) \mapsto \left( \frac{\rho}{ \max(|\cos \theta|, |\sin \theta|)}, \theta\right).$
- The graph of a differentiable function is homeomorphic to the domain of the function.
- A differentiable parametrization of a curve is a homeomorphism between the domain of the parametrization and the curve.
- A chart of a manifold is a homeomorphism between an open subset of the manifold and an open subset of a Euclidean space.
- The stereographic projection is a homeomorphism between the unit sphere in `{{tmath|\R^3}}`{=mediawiki} with a single point removed and the set of all points in `{{tmath|\R^2}}`{=mediawiki} (a 2-dimensional plane).
- If $G$ is a topological group, its inversion map $x \mapsto x^{-1}$ is a homeomorphism. Also, for any $x \in G,$ the left translation $y \mapsto xy,$ the right translation $y \mapsto yx,$ and the inner automorphism $y \mapsto xyx^{-1}$ are homeomorphisms.
### Counter-examples {#counter_examples}
- and `{{tmath|\R^n}}`{=mediawiki} are not homeomorphic for `{{math|1=''m'' ≠ ''n''.}}`{=mediawiki}
- The Euclidean real line is not homeomorphic to the unit circle as a subspace of `{{tmath|\R^2}}`{=mediawiki}, since the unit circle is compact as a subspace of Euclidean `{{tmath|\R^2}}`{=mediawiki} but the real line is not compact.
- The one-dimensional intervals $[0,1]$ and $(0,1)$ are not homeomorphic because one is compact while the other is not.
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# Homeomorphism
## Properties
- Two homeomorphic spaces share the same topological properties. For example, if one of them is compact, then the other is as well; if one of them is connected, then the other is as well; if one of them is Hausdorff, then the other is as well; their homotopy and homology groups will coincide. Note however that this does not extend to properties defined via a metric; there are metric spaces that are homeomorphic even though one of them is complete and the other is not.
- A homeomorphism is simultaneously an open mapping and a closed mapping; that is, it maps open sets to open sets and closed sets to closed sets.
- Every self-homeomorphism in $S^1$ can be extended to a self-homeomorphism of the whole disk $D^2$ (Alexander\'s trick).
## Informal discussion {#informal_discussion}
The intuitive criterion of stretching, bending, cutting and gluing back together takes a certain amount of practice to apply correctly---it may not be obvious from the description above that deforming a line segment to a point is impermissible, for instance. It is thus important to realize that it is the formal definition given above that counts. In this case, for example, the line segment possesses infinitely many points, and therefore cannot be put into a bijection with a set containing only a finite number of points, including a single point.
This characterization of a homeomorphism often leads to a confusion with the concept of homotopy, which is actually *defined* as a continuous deformation, but from one *function* to another, rather than one space to another. In the case of a homeomorphism, envisioning a continuous deformation is a mental tool for keeping track of which points on space *X* correspond to which points on *Y*---one just follows them as *X* deforms. In the case of homotopy, the continuous deformation from one map to the other is of the essence, and it is also less restrictive, since none of the maps involved need to be one-to-one or onto. Homotopy does lead to a relation on spaces: homotopy equivalence.
There is a name for the kind of deformation involved in visualizing a homeomorphism. It is (except when cutting and regluing are required) an isotopy between the identity map on *X* and the homeomorphism from *X* to *Y*
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# Hvergelmir
**Hvergelmir** (Old Norse \"bubbling boiling spring\") is an important primal wellspring in Norse mythology. Hvergelmir is attested in the *Poetic Edda*, compiled in the 13th century from earlier traditional sources, and the *Prose Edda*, written in the 13th century by Snorri Sturluson. In the *Poetic Edda*, Hvergelmir is mentioned in a single stanza, which details that it is the location where liquid from the antlers of the stag Eikþyrnir flow, and that the spring, \"whence all waters rise\", is the source of numerous rivers. The *Prose Edda* repeats this information and adds that the spring is located in Niflheim, that it is one of the three major springs at the primary roots of the cosmic tree Yggdrasil (the other two are Urðarbrunnr and Mímisbrunnr), and that within the spring are a vast amount of snakes and the dragon Níðhöggr.
## Attestations
Hvergelmir is attested in the following works:
### *Poetic Edda* {#poetic_edda}
Hvergelmir receives a single mention in the *Poetic Edda*, found in the poem *Grímnismál*:
+------------------------------------------------+---+
| : Eikthyrnir the hart is called, | |
| : that stands o\'er Odin\'s hall, | |
| : and bites from Lærad\'s branches; | |
| : from his horns fall drops into Hvergelmir, | |
| : whence all waters rise: | |
+------------------------------------------------+---+
This stanza is followed by three stanzas consisting mainly of the names of 42 rivers. Some of these rivers lead to the dwelling of the gods (such as Gömul and Geirvimul), while at least two (Gjöll and Leipt), reach to Hel.
### *Prose Edda* {#prose_edda}
Hvergelmir is mentioned several times in the *Prose Edda*. In *Gylfaginning*, Just-as-High explains that the spring Hvergelmir is located in the foggy realm of Niflheim: \"It was many ages before the earth was created that Niflheim was made, and in its midst lies a spring called Hvergelmir, and from it flows the rivers called Svol, Gunnthra, Fiorm, Fimbulthul, Slidr and Hrid, Sylg and Ylg, Vid, Leiptr; Gioll is next to Hell-gates.\"
Later in *Gylfaginning*, Just-as-High describes the central tree Yggdrasil. Just-as-High says that three roots of the tree support it and \"extend very, very far\" and that the third of these three roots extends over Niflheim. Beneath this root, says Just-as-High, is the spring Hvergelmir, and that the base of the root is gnawed on by the dragon Níðhöggr. Additionally, High says that Hvergelmir contains not only Níðhöggr but also so many snakes that \"no tongue can enumerate them\".
The spring is mentioned a third time in *Gylfaginning* where High recounts its source: the stag Eikþyrnir stands on top of the afterlife hall Valhalla feeding branches of Yggdrasil, and from the stag\'s antlers drips great amounts of liquid down into Hvergelmir. High tallies 26 rivers here.
Hvergelmir is mentioned a final time in the *Prose Edda* where Third discusses the unpleasantries of Náströnd. Third notes that Hvergelmir yet worse than the venom-filled Náströnd because---by way of quoting a portion of a stanza from the *Poetic Edda* poem *Völuspá*---\"There Nidhogg torments the bodies of the dead\"
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# Hawar Islands
The **Hawar Islands** (*جزر حوار*; transliterated: *Juzur Ḥawār*) are an archipelago of desert islands; all but one are owned by Bahrain, while the southern, small, and uninhabited Jinan Island (Arabic: جزيرة جينان; transliterated: *Jazirat Jinan*) is administered by Qatar as part of its Al-Shahaniya municipality. The archipelago is situated off the west coast of Qatar in the Gulf of Bahrain of the Persian Gulf.
## Description
The islands used to be one of the settlements of the Bahraini branch of the Dawasir who settled there in the early 19th century. The islands were first surveyed in 1820, when they were called the Warden\'s Islands, and two villages were recorded. They are now uninhabited, other than a police garrison and a hotel on the main island; access to all but Hawar island itself is severely restricted. Local fishermen are allowed to fish in adjacent waters and there is some recreational fishing and tourism on and around the islands. Fresh water has always been scarce; historically it was obtained by surface collection and even today, with the desalination plant, additional supplies have to be brought in.
## Geography
Despite their proximity to Qatar (they are only about 1 nmi from the Qatari mainland whilst being about 10 nmi from the main islands of Bahrain), most of the islands belong to Bahrain, having been a part of a dispute between Bahrain and Qatar which was resolved in 2001. The islands were formerly coincident with the district or *Minṭaqat* Juzur Ḥawār (مِنْطَقَة جُزُر حَوَار) and are now administered as part of the Southern Governorate of Bahrain. The land area of the islands is approximately 52 km2.
Although there are 36 islands in the group, many of the smaller islands are little more than sand or shingle accumulations on areas of exposed bedrock molded by the ongoing processes of sedimentation and accretion. The World Heritage Site application`{{clarify|date=July 2020}}`{=mediawiki} named 8 major islands, which conforms to`{{clarify|date=July 2020}}`{=mediawiki} the description of the islands when first surveyed as consisting of 8 or 9 islands. It has often been described as an archipelago of 16 islands. Janan Island, to the south of Hawar island, is not legally considered to be a part of the group and is owned by Qatar.
## Flora and fauna {#flora_and_fauna}
There are small herds of Arabian oryx and sand gazelle on Hawar island, and the seas around support sea turtles and a large population of dugongs.
The islands are home to many bird species. The archipelago has been designated an Important Bird Area by BirdLife International because it supports significant populations of western reef egrets, Socotra cormorants (with some 200,000--300,000 adults recorded in 1992, making it the largest known breeding concentration in the world), Saunders\'s and white-cheeked terns, and sooty falcons. Other breeding birds include Caspian and bridled terns, and ospreys. Wintering birds include great crested grebes and greater flamingos.
### Conservation
The islands were listed as a Ramsar site in 1997. In 2002, the Bahraini government applied to have the islands recognised as a World Heritage Site due to their unique environment and habitat for endangered species; the application was ultimately unsuccessful.
## Administration
The islands were formerly coincident with the region or *Minṭaqat* of Juzur Ḥawār (مِنْطَقَة جُزُر حَوَار) and are now administered as part of the Southern Governorate of Bahrain.
Jinan Island is administered as part of Al-Shahaniya Municipality of Qatar.
## Access
The islands are home to numerous birds, oryx, gazelles, and Socotra cormorants. The islands are connected through a 25 km ferry ride from Manama and are reported to have a potential to be developed as a beach tourism destination.
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# Hawar Islands
## List of islands {#list_of_islands}
### Hawar archipelago {#hawar_archipelago}
By far the largest island is Hawar, which accounts for more than 41 km2 of the 54.5 km2 land area. Following in size are Suwād al Janūbīyah, Suwād ash Shamālīyah, Rubud Al Sharqiyah, Rubud Al Gharbiyah, and Muhazwarah (Umm Hazwarah).
Name Arabic Coordinates Max height Comments
--------------------------------- --------------- ------------- ------------ -----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
Hawar جَزِيرَة حَوَار The island is 18 km long and varies in width from 5.2 to 0.9 km. Continuous beach ridge complex west coast, sloping bedrock rising west to east. Complex bay and cliff formations east coast fronted in places by subqa, jebel and terminals of east lower headlands aeolian formations calcified reef structures and algal mats.
Suwād al Janūbīyah سُوَاد اَلْجَنُوبِيَّة South Suwad. Sand and shingle accumulations, subqa and salt-encrusted flats with areas of exposed surface rock, beach rock to the north. Mud, shoals and shallow to south, blown sand beaches. Host to a large Socotra cormorant colony, representing over 10% of the world population.
Suwād ash Shamālīyah سُوَاد اَلشَّمَالِيَّة North Suwad. Sand and shingle accumulations, subqa and salt-encrusted flats, areas of beach rock to north, shoals and shallow to south and southeast, wind blown sand, beaches.
Rubud Al Sharqiyah رَبَض اَلشَّرْقِيَّة East Rubud. Sand and shingle accumulations, subqa and salt-encrusted flats, storm beach north and northeast, mudflats, shoals and shallow lagoons south and east large areas of beach rock and reef. Islands off exposed beach rocks & vegetated islets. Significant western reef heron colony.
Rubud Al Gharbiyah رَبَض اَلْغَرْبِيَّة West Rubud. Sand and shingle accumulations, subqa and encrusted flats, storm beach north and west, mudflats, shoals and shallow lagoons south and east. Islands off exposed beach rocks & vegetated islets. Significant western reef heron colony.
Muhazwarah (Umm Hazwarah) Rock (exposed strata), undercut cliffs, small sand or shingle beaches, raised marine terraces with sand spit southern aspect sand accumulations behind. Centre open wadi with rim rocks.
Umm Jinni أم جني Sand and shingle accumulations with areas of beach rock shoals and shallow lagoons surrounding.
Ajirah جَزِيرَة عَجِيرَة Rock (exposed strata), undercut cliffs and areas of beach rock and reefs. Single marine terrace with sand spit southwest sand and shingle accumulations behind.
Bū Sadād (Bu Sa'adad) (*group*) جُزُر بُو سَدَاد Sand and shingle accumulations with areas of beach rock, shoals and shallow lagoons surrounding. Storm beaches northern aspects. Islands off ‑ various with mud sand and exposed rocky vegetated islets.
Al Hajiyat (*group*) الحجيات Group of 3 islands. Rock (exposed strata), undercut cliffs terraced, small sand or shingle beaches, reefs.
Al Wukūr (Al Wakur) (*group*) جُزُراَلْوُكُور Isolated sea stacks with shingle beaches with surrounding shallow lagoon.
Bu Tammur (*group*) بو تمور Isolated undercut heavily fossilized rock platforms.
The following were not considered as part of the Hawar islands in the International Court of Justice (ICJ) judgment, being located between Hawar and the Bahrain Islands and not disputed by Qatar, but have been included in the Hawar archipelago by the Bahrain government as part of the 2002 World Heritage Site application.
Name Arabic Coordinates Max height Comments
--------------------------- ------------- ------------- ------------ ---------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
Jazīrat Mashtān (Mashtan) جَزِيرَة مَشْتَان Northernmost island and the closest to Bahrain Island. Roughly equidistant between there and the northernmost of the Hawar islands, Rubud Al Gharbiyah. Although very small at high tide, at low tide Mashtan is considerably larger.
Al Mu\`tariḑ اَلْمُعْتَرِض A reef south-east of Mashtan. Location of the largest sighting of dugong in the area.
Fasht Bū Thawr (Bu Thur) فَشْت بُو ثَوْر A low-tide elevation coral reef approximately 100 m long.
### Janan Island {#janan_island}
Janan (or Jinan) Island, a small island south of Hawar island, was also considered in the 2001 `{{abbr|ICJ|International Court of Justice}}`{=mediawiki} judgment. Based on a previous agreement when both Qatar and Bahrain were under British occupation, it was judged to be separate from the Hawar islands and so considered by the court separately. It was awarded to Qatar.
Name Arabic Coordinates Max height (meters) Comments
----------------------- ------------ ------------- --------------------- ----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
Jazīrat Jinān (Janan) جَزِيرَة جَنَان A small island (or islands, if the low tide elevation of Hadd Janan is counted separately), 1.6 nmi south of Hawar Island. It measures approximately 700 by and with a total surface area of around 0.115 km2
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# Henry Ainsworth
**Henry Ainsworth** (1571--1622) was an English Nonconformist clergyman and scholar. He led the Ancient Church, a Brownist or English Separatist congregation in Amsterdam alongside Francis Johnson from 1597, and after their split led his own congregation. His translations of and commentaries on the Hebrew scriptures were influential for centuries.
## Separatist career {#separatist_career}
Ainsworth was born of a farming family of Swanton Morley, Norfolk. He was educated at St John\'s College, Cambridge, later moving to Caius College, but left without a degree. After associating with the Puritan party in the Church, he joined the Brownists, but submitted to the Church of England after being arrested in London, and again when he was arrested in Ireland.
By 1597, Ainsworth moved to Amsterdam and found a home in \"a blind lane at Amsterdam\", working as porter to a bookseller, and lived in severe poverty. According to Roger Williams, Ainsworth 'lived on 9d a week with roots boiled'. When the pastor Francis Johnson came to the church from London, where he had been in prison, Ainsworth was elected as teacher (or doctor), thanks to his knowledge of Hebrew.
Ainsworth attempted to arbitrate the quarrel between Francis and Thomasine Johnson on the one side and his brother George Johnson on the other, where George accused Thomasine of dressing immodestly and Francis of ruling the church tyrannically. Though he may initially have sympathised with George, on 15 January 1598, Ainsworth chaired a church meeting which censured him. Francis and Ainsworth also ex-communicated their elder Matthew Slade for refusing to stop going to services in the Dutch Reformed Church. Ainsworth himself caused some scandal when it emerged that he had twice submitted to the Church of England, but he was not disciplined.
Though often involved in controversy, Ainsworth was not arrogant, but was a steadfast and cultured champion of the principles represented by the early Congregationalists. Amid all the controversy, he steadily pursued his studies. The combination was so unique that some have mistaken him for two different individuals. Confusion has also been occasioned through his friendly controversy with one John Ainsworth, who left the Anglican for the Roman Catholic church.
In 1604, Johnson and Ainsworth wrote a petition for toleration of their church and took it to England in the hope of delivering it to James I. In their attempts to get it to the king, they rewrote it twice, and on their return to Amsterdam published all three versions under the title *An Apologie or Defence of svch trve Christians as are commonly (vnjustly) called Brovvnists.*
In 1610, Johnson changed his mind about the democratic Congregational structure of the Ancient Church, arguing that authority lay with the ministers, not the people. After nearly a year of debate, on 15 December, Ainsworth and his followers split from Johnson, and successfully sued them for possession of the church building. John Robinson tried to mediate between the two factions, but ended up taking Ainsworth\'s side.
In 1620, after Johnson\'s church had departed for North America, but before Robinson\'s had left on the *Mayflower*, Ainsworth\'s church considered joining the latter in their journey and put some money into the project. Robert Cushman criticised the proposal, saying \'Our liberty is to them as ratsbane, and their rigour as bad to us as the Spanish Inquisition.\' Though nothing came of the plan, the Ainsworth church still waved the pilgrims off from Leiden.
## Personal life {#personal_life}
On 29 April 1607, Ainsworth married Marjory Appelbey, a widow from Ipswich with one daughter. In 1612, the elder in the Ancient Church, Daniel Studley, was accused of 'many lascivious attempts' the girl, and confessed to having \'clapped\' her.
Henry Ainsworth died in 1622, leaving unfinished work on works on Hosea, Matthew and Hebrews.
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# Henry Ainsworth
## Works
Ainsworth was one of the most able apologists of the so-called Brownist movement. His first solo work *The communion of saincts* (1607) is summarised by the historian of Separatism Stephen Tomkins as arguing \'that the true church is a holy community while a church that incorporates the entire population is neither holy nor a community\'. Tomkins describes his second book *Covnterpoyson* (1608) as \'the most compelling apologia that the Separatist movement ever produced\'. It was written in reply to the puritan minister John Sprint and to Richard Bernard\'s *The Separatist Schisme*.
Ainsworth also wrote reply to John Smyth, the Puritan leader who adopted credobaptism, entitled *Defence of Holy Scripture, Worship and Ministry used in the Christian Churches separated from Antichrist, against the Challenges, Cavils and Contradictions of Mr Smyth* (1609). Of Smyth\'s progression to concluding credobaptism, Ainsworth said he \'had gone 'from error to error, and now at last to the abomination of Anabaptism', which 'in him was the worship ... of the devil'.
His scholarly works include his *Annotations*---on *Genesis* (1616); *Exodus* (1617); *Leviticus* (1618); *Numbers* (1619); *Deuteronomy* (1619); *Psalms* (including a metrical version, 1612); and the *Song of Solomon* (1623). These were collected in folio in 1627. From the outset the *Annotations* took a commanding place, especially among continental scholars, establishing a scholarly tradition for English nonconformity. Tomkins notes that \'as late as 1866, W.S. Plumer\'s commentary on Psalms cited Ainsworth as an authority more than a hundred times and the 1885 (English) Revised Version of the Bible drew on his work.\'
His publication of Psalms, *The Book of Psalmes: Englished both in Prose and Metre with Annotations* (Amsterdam, 1612), which includes thirty-nine separate monophonic psalm tunes, constituted the Ainsworth Psalter, the only book of music brought to New England in 1620 by the Pilgrim settlers. Although its content was later reworked into the Bay Psalm Book, it had an important influence on the early development of American psalmody. An early critic of the Brownists said that 'by the uncouth and strange translation and metre used in them, the congregation was made a laughing stock', while the 1885 *Dictionary of National Biography* said that Ainsworth 'had not the faintest breath of poetical inspiration'.
Ainsworth died in 1622, or early in 1623, for in that year was published his *Seasonable Discourse, or a Censure upon a Dialogue of the Anabaptists*, in which the editor speaks of him as a departed worthy
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# Hernando de Alarcón
**Hernando de Alarcón** (born `{{c.}}`{=mediawiki} 1500) was a Spanish explorer and navigator of the 16th century, noted for having led a 1540 expedition to the Colorado River Delta, during which he became one of the first Europeans to ascend the Colorado River from its mouth and became the first European to see Alta California.
Little is known about Alarcón\'s life outside of his exploits in New Spain. He was probably born in the town of Trujillo, in present-day Extremadura, Spain, in the first years of the 16th century and travelled to the Spanish colonies in the Americas as a young man.
## 1540 expedition
By 1540, Mexico had been conquered and state-sponsored expeditions were being sent north in search of new wealth and the existence of a water passage between the Atlantic and Pacific oceans. Viceroy of New Spain Antonio de Mendoza commissioned Francisco Vázquez de Coronado to undertake a massive overland expedition to find the Seven Cities of Cibola, which were rumoured to exist in the unexplored northern interior. The expedition was to be resupplied with stores and provisions delivered by ships traveling north up the Sea of Cortés (Gulf of California), the commander of which would be Alarcón.
Alarcón set sail from the Pacific port of Acapulco with two ships, the *San Pedro* and the *Santa Catalina*, on May 9, 1540, and was later joined by the *San Gabriel* at St. Jago de Buena Esperanza (modern-day Manzanillo, Colima). His orders from Mendoza were to await the arrival of Coronado\'s land expedition at a certain latitude along the coast. The meeting with Coronado was never effected, though Alarcón reached the appointed place and left letters, which were soon afterward discovered by Melchor Díaz, another explorer.
Alarcón eventually sailed to the northern terminus of the Gulf of California and completed the explorations begun by Francisco de Ulloa the preceding year. During this voyage Alarcón proved to his satisfaction that no open-water passage existed between the Gulf of California and the Pacific Ocean (then called the \"South Sea\"). Subsequently, on September 26, he entered the mouth of the Colorado River, which he named the *Buena Guía* (\"good guide\"). He was the first European to ascend the river for a distance considerable enough to make important observations. On a second voyage, he probably proceeded past the present-day site of Yuma, Arizona. A map drawn by one of Alarcón\'s pilots is the earliest accurately detailed representation of the Gulf of California and the lower course of the Colorado River.
Alarcón is unusual among 16th-century *conquistadores* for his reportedly humane treatment of the Indians he met, as opposed to the often reckless and cruel behavior known from accounts of his contemporaries. Bernard de Voto, in his 1953 *Westward the Course of Empire*, observed: \"The Indians had an experience they were never to repeat: they were sorry to see these white men leave.\" Alarcón wrote of his contact with the Yuma-speaking Indians along Colorado. The information he compiled consisted of their practices in warfare, religion, curing, and even sexual customs.
California Historical Landmark No. 568, on the west bank of the Colorado River near Andrade in Imperial County, California, commemorates Alarcón\'s expedition had been the first non-Indians to sight land within the present-day state of California.
## California Historical Landmark {#california_historical_landmark}
California Historical Landmark number 568 reads:
: *NO. 568 HERNANDO DE ALARCÓN EXPEDITION - Alarcón\'s mission was to provide supplies for Francisco Coronado\'s expedition in search of the fabled Seven Cities of Cibola. The Spaniards led by Hernando de Alarcón ascended the Colorado River by boat from the Gulf of California past this point, thereby becoming the first non-Indians to sight Alta California on September 5, 1540
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# Hunan cuisine
**Hunan cuisine**, also known as **Xiang cuisine**, consists of the cuisines of the Xiang River region, Dongting Lake and western Hunan Province in China. It is one of the Eight Great Traditions of Chinese cuisine and is well known for its hot and spicy flavours, fresh aroma and deep colours. Despite this, only about 20% of the cuisine uses capsicum to produce a strong spicy taste. Common cooking techniques include stewing, frying, pot-roasting, braising and smoking. Due to the high agricultural output of the region, ingredients for Hunan dishes are many and varied.
## History
The history of the cooking skills employed in Hunan cuisine dates back to the 17th century. The first mention of chili peppers in local gazettes in the province date to 1684, 21st year of the Kangxi Emperor. During the course of its history, Hunan cuisine assimilated a variety of local forms, eventually evolving into its own style. Some well-known dishes include fried chicken with Sichuan spicy sauce (`{{zh|s=麻辣鸡丁|t=麻辣雞丁|p=málà jīdīng|labels=no}}`{=mediawiki}) and smoked pork with dried long green beans (`{{zh|s=干豆角蒸腊肉|t=乾豆角蒸臘肉|p=gāndòujiǎo zhēng làròu|labels=no}}`{=mediawiki}).
Hunan cuisine consists of three primary styles:
- Xiang River style: Originating from Changsha, Xiangtan and Hengyang. The dishes are quite oily with a attractive colour, and the dishes are spicy, fresh, and have a strong aroma. Dishes include Stir-fry chicken with Chili, Braised Meat with Black Bean Sauce and Changsha Stinky Tofu.
- Dongting Lake style: Originating from Yueyang, Yiyang and Changde. This style is also oily but is also starchy, accompanied with spiciness and saltiness. Stewing is more common in this form of Hunan cuisine, and fish is commonly used too. Notable dishes include Dongting Gold Tortoise and Lotus Seedpod with Crystal Sugar.
- Western Hunan style: Originating from Zhangjiajie, Jishou and Huaihua. Preserved meats and pickled vegetables are more commonly used. The taste is influenced by the ethnic minorities in the region, which results in a sour, spicy, and salty taste. Notable dishes include braised mushrooms and Xiangxi Sour Meat.
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# Hunan cuisine
## Features
With its liberal use of chili peppers, shallots and garlic, Hunan cuisine is known for being *gan la* (`{{zh|c=干辣|p=gān là|l=dry and spicy|labels=no}}`{=mediawiki}) or purely hot, as opposed to Sichuan cuisine, to which it is often compared. Sichuan cuisine uses its distinctive *ma la* (`{{zh|c=麻辣|p=má là|l=spicy and numbing|labels=no}}`{=mediawiki}) seasoning and other complex flavour combinations, frequently employs Sichuan pepper along with chilies which are often dried. It also utilises more dried or preserved ingredients and condiments. Hunan cuisine, on the other hand, is often spicier by pure chili content and contains a larger variety of fresh ingredients. Both Hunan and Sichuan cuisine are perhaps significantly oilier than the other cuisines in China, but Sichuan dishes are generally oilier than Hunan dishes. Another characteristic distinguishing Hunan cuisine from Sichuan cuisine is that Hunan cuisine uses smoked and cured goods in its dishes much more frequently.
Hunan cuisine\'s menu changes with the seasons. In a hot and humid summer, a meal will usually start with cold dishes or a platter holding a selection of cold meats with chilies for opening the pores and keeping cool in the summer. In winter, a popular choice is hot pot, thought to heat the blood in the cold months. A special hot pot called *yuanyang huoguo* (`{{zh|s=鸳鸯火锅|t=鴛鴦火鍋|p=yuānyāng hǔogūo|l=[[Mandarin duck#Chinese culture|Mandarin ducks]] hot pot|labels=no}}`{=mediawiki}) is notable for splitting the pot into a spicy and a mild side. One of the classic dishes in Hunan cuisine served in restaurants and at home is farmer pepper fried pork. It is made with several common ingredients: pork belly, green pepper, fermented black beans and other spices.
## List of notable dishes {#list_of_notable_dishes}
English Traditional Chinese Simplified Chinese Pinyin Notes
------------------------------------------------ --------------------- -------------------- ------------------------ -------
Changsha-style rice vermicelli
Changde-style stewed beef with rice vermicelli
Changsha stinky tofu
Cured ham with cowpeas
Dong\'an chicken
\"Dry-wok\" chicken
Home-style tofu
Lotus seeds in rock sugar syrup
Mao\'s braised pork
Mala chicken
Mashed shrimp in lotus pod
Pearly meatballs
Pumpkin cake
Sautéed pork with chili pepper
Smoky flavours steamed together
Spare ribs steamed in bamboo
Spicy crawfish 香辣口味蝦 香辣口味虾 *xiāng là kǒu wèi xiā*
Steamed fish head in chili sauce
Stir fried duck blood
Stir fried meat with douchi and chili peppers
Yongfeng chili sauce
A discussion of Hunan cuisine overall may list a number of piquant dishes, usually but not always very hot and spicy
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# Hilversum
**Hilversum** (`{{IPA|nl|ˈɦɪlvərsʏm|-|Nl-Hilversum.ogg}}`{=mediawiki}) is a city and municipality in the province of North Holland, Netherlands. Located in the heart of the Gooi, it is the largest urban centre in that area. It is surrounded by heathland, woods, meadows, lakes and smaller towns. Hilversum is part of the Randstad, one of the largest conurbations in Europe, and the Amsterdam metropolitan area; it is about 22`{{spaces}}`{=mediawiki}km southeast of Amsterdam\'s city centre and about 15`{{spaces}}`{=mediawiki}km north of Utrecht.
The city is home to several major radio, television, and newspaper companies such as *Nederlandse Omroep Stichting*. Hilversum is thus known for being the *mediastad* (media city) of the Netherlands.
## Town
Hilversum lies 24 km south-east of Amsterdam and 15 km north of Utrecht. The town is known for its architecturally important Town Hall (Raadhuis Hilversum), designed by Willem Marinus Dudok and built in 1931.
Hilversum has one public library, two swimming pools (Van Hellemond Sport and De Lieberg), several sports halls, and several shopping centers (such as Hilvertshof, Winkelcentrum Kerkelanden, De Riebeeckgalerij, and Winkelcentrum Seinhorst). Locally, the town center is known as `{{lang for|nl|het dorp|the village}}`{=mediawiki}.
## Geography
Hilversum is located on the sandy, hilly parts of the Gooi region and has four hills: the Boomberg (closest to the town center); the Trompenberg (now a luxury residential area), the Hoorneboeg (farther to the south), and two kilometers east of there, the Zwaluwenberg (25`{{spaces}}`{=mediawiki}m), home to the headquarters of the inspector-general of the armies since 1950. These hills date from the period of the Ice-age, when Hilversum was the southern-most point covered by glaciers.
The surrounding towns of Hilversum are Nieuw-Loosdrecht, Bussum, Kortenhoef, Blaricum, Hollandsche Rading, Lage Vuursche, Maartensdijk, \'s-Graveland, Laren, Nederhorst den Berg, and Ankeveen.
Hilversum consists of the following districts and neighborhoods: Center (Langgewenstbuurt, Sint Vitusbuurt, Havenstraatbuurt, and Centrum), Northwest (Nimrodpark, Trompenberg North, Trompenberg South, Media Park, Raadhuiskwartier, and Boomberg), Northeast (North, Johannes Geradtswegbuurt, Erfgooiersbuurt, and AZC Crailo), East (Geuzenbuurt, Electrobuurt, Astronomiebuurt, Science neighborhood, Kamrad, Kleine Driftbuurt and Liebergen), Southeast (Bloemkwartier Noord, Bloemenkwartier Zuid, Schilderskwartier, \'t Hoogt van\' t Kruis, Arenaparkkwartier and West Indiëkwartier), Zuid (Schrijverskwartier, Staatsliedenkwartier and Zeeheldenkwartier), Southwest (Kerkelanden, Havenkwartier, Zeverijn and Het Rode Dorp) and Hilversumse Meent. In 1767, Hilversum was still divided into 4 districts (quarters): the Neuquartier, Groestquartier, Kerkquartier, and the Sandtbergerquartier.
The Oude Haven in the southwest is at the end of the Gooische Vaart. The construction of the canal between \'s-Graveland and Hilversum was done in stages over 240 years. The canal was completed in 1876. Later, a modern harbor was dug, surrounded by an industrial estate. There is also a leisure harbor.
## International
Hilversum has a variety of international schools, such as the *Violenschool* and *International School Hilversum \"Alberdingk Thijm\"*. Also, Nike\'s, Hunkemöller\'s`{{Circular reference|date=March 2019}}`{=mediawiki} and Converse\'s European headquarters are located in Hilversum.
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# Hilversum
## History
Earthenware found in Hilversum gives its name to the Hilversum culture, which is an early- to mid-Bronze Age, or 1800--1200 BC material culture. Artifacts from this prehistoric civilization bear similarities to the Wessex Culture of southern Britain and may indicate that the first Hilversum residents emigrated from that area.
The first brick settlements formed around 900, but it was not until 1305 that the first official mention of Hilversum (\"Hilfersheem\" from \"Hilvertshem\" meaning \"houses between the hills\") was found. At that time it was a part of Naarden, the oldest town in the Gooi area.
Farming, raising sheep, and wool manufacturing were the main sources of income for inhabitants of the Gooi region in the Middle Ages. In 1424, Hilversum received its first official independent status. This made further growth possible because permission was no longer needed from neighboring Naarden for new industrial development.
The town grew further in the 17th century when the Dutch economy was strong, and several canals were built connecting it indirectly to Amsterdam.
In 1725 and 1766 large fires destroyed most of the town, leveling parts of the old townhouse and the church next to it. The town overcame these setbacks and the textile industry continued to develop, among other ways by devising a way to weave cows\' hair.
In the 19th century a substantial textile and tapestry industry emerged, aided by a railway link to Amsterdam in 1874. From that time onward the town grew quickly with wealthy commuters from Amsterdam moving in, building themselves large villas in the wooded surroundings, and gradually starting to live in Hilversum permanently. Despite this growth, Hilversum was never granted city rights so it is still referred to by many locals as \"het dorp\", or \"the village.\"
For the 1928 Summer Olympics in neighboring Amsterdam, it hosted all of the non-jumping equestrian and the running part of the modern pentathlon event.
The *Nederlandse Seintoestellen Fabriek* (NSF) company established a professional transmitter and radio factory in Hilversum in the early 1920s, growing into the largest of its kind in the Netherlands.
Following the defeat of Allied forces in the Netherlands in 1940, and its occupation by Nazi Germany, Hilversum became the headquarters of the German Army (*Heer*) in the Netherlands. On February 25 and 26, 1941, most of Hilversum\'s factories went on strike against the start of the Holocaust in the so-called February strike (Amsterdam Docker\'s Strike). Some 10,000 people took part. The Holocaust took the lives of 2,000 Hilversum Jews and the community never fully recovered. Since 2015 there has been an annual remembrance service. Some 50 Hilversummers were awarded the title of Righteous among the nations from Yad Vashem, including Victor Kugler, one of Anne Frank\'s helpers.
In 1948, NSF was taken over by Philips. However, Dutch radio broadcasting organizations (followed by television broadcasters during the 1950s) centralised their operations in Hilversum, providing a source of continuing economic growth. The concentration of broadcasters in Hilversum has given it its enduring status as the media city for the Netherlands.
In 1964, the population reached a record high of over 103,000. However, the textile industry had started its decline; only one factory, Veneta, managed to continue into the 1960s, when it also had to close. Another major industry, the chemical factory IFF, also closed by the end of the 1960s.
After the 1960s, the population gradually declined, until stabilising at around 86,000 in 2006 and rising to 90,000 in 2018. Several factors other than the slump in manufacturing contributed to this decline: one is the reduction in average family size, with fewer people living in each house; second, the town is virtually unable to expand because much surrounding land was sold by city architect W.M. Dudok to the Goois Natuurreservaat (*nl*); third, the rapid increase in property values forced many people to move to less expensive areas in the Netherlands.
Hilversum was one of the first towns to have a local party of the populist movement called *Leefbaar* (\"liveable\"). Founded by former social-democrat Jan Nagel, it was initially held at bay for alderman positions. In 2001, Nagel from Leefbaar Hilversum teamed up with Leefbaar Utrecht leaders to found a national Leefbaar Nederland party.
The town has undertaken many improvements, including renovating its central train station, renovation of the main shopping centre (Hilvertshof), and development of new dining and retail districts downtown including the \"vintage\" district in the Leeuwenstraat. Several notable architectural accomplishments include the Institute for Sound and Vision, and Zanderij Crailoo (*nl*), the largest man-made wildlife crossing in the world.
The nearby Media Park was the scene of the 2002 assassination of politician Pim Fortuyn; in 2015, a gunman carrying a false pistol stormed into Nederlandse Omroep Stichting\'s headquarters, demanding airtime on the evening news.
## Culture
There is the large Catholic neo-gothic St. Vitus church (P.J.H. Cuypers, 1892, bell tower 96 m. The city played host to many landscape artists during the 19th century, including Barend Cornelis Koekkoek.
In the 1950s and 1960s the city played host to a major European Tennis tournament.
The 1958 Eurovision Song Contest took place in Hilversum. In 2020 the international television event *Eurovision: Europe Shine a Light* was broadcast from Studio 21 in Hilversum\'s Media Park. This event was held in place of the Eurovision Song Contest 2020 which was cancelled due to the COVID-19 pandemic.
### Broadcasting
Hilversum is often called \"media city\", since it is the principal centre for radio and television broadcasting in the Netherlands, and is home to an extensive complex of radio and television studios and to the administrative headquarters of the multiple broadcasting organizations which make up the Netherlands Public Broadcasting system. Hilversum is also home to many newer commercial TV production companies. Radio Netherlands, which had been broadcasting worldwide via shortwave radio since the 1920s, was also based in Hilversum until it was dissolved in 2013.
The following is a list of organizations that have, or are continuing to, broadcast from studios in Hilversum:
One result of the town\'s history as an important radio transmission centre is that many older radio sets throughout Europe featured *Hilversum* as a pre-marked dial position on their tuning scales.
Dutch national voting in the Eurovision Song Contest is normally co-ordinated from Hilversum.
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# Hilversum
## Transport
### Airport
Hilversum Airport is located in the southwest of the municipality. Next to it is the former Marine Training Camp (MOK), now Corporal Van Oudheusden Barracks for the medical troops. In wartime the airfield was expanded significantly by the German military. They also set up an assembly line for training aircraft, produced by Fokker in Weesp.
### Railway
Hilversum is well connected to the Dutch railway network, and has three stations.
Station Notes
---------------------- -------------------------------------------------------------------------------------------------------------------------------------------------------
Hilversum Opened on 10 June 1874. Served by regional, Intercity and international trains.
Hilversum Media Park Opened on 26 May 1974. Previously named Hilversum NOS (1974--1989) and Hilversum Noord (1989--2013). Only served by regional trains.
Hilversum Sportpark Opened on 1 June 1886. Previously named Amersfoortsche Straatweg (1886--1919) and Soestdijker Straatweg (1919--1965). Only served by regional trains.
### Public buses {#public_buses}
Most local and regional buses are operated by Connexxion, but two of the bus routes are operated by Syntus Utrecht and two others by U-OV and Pouw Vervoer. Regional bus route 320 is operated by both Connexxion and Pouw Vervoer. In 2018, major road works started to make room for a new BRT bus lane from Hilversum to Huizen, set to open in early 2021.
#### Local bus lines {#local_bus_lines}
Line Route Operator Notes
------ --------------------------------------------------------------------------------- ------------ -------
1 Hilversum Station - Centrum (Downtown) - Kerkelanden Connexxion
2 Hilversum Station - Over \'t Spoor - Erfgooiers Connexxion
3 Hilversum Station - Hilversum Sportpark Station - Tergooi Ziekenhuis (Hospital) Connexxion
#### Regional bus lines {#regional_bus_lines}
Line Route Operator Notes
------ ------------------------------------------------------------------------------------------------------------------------------------------------------------------ ------------------------------------------------------------------------ ------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
58 Hilversum Station - Hollandsche Rading - Maartensdijk - Bilthoven - De Bilt - Zeist U-OV and Pouw Vervoer Mon-Sat during daytime hours only. U-OV operates this route during weekdays, Pouw Vervoer on Saturdays.
59 Hilversum Station - Lage Vuursche - Den Dolder - Huis ter Heide - Zeist U-OV and Pouw Vervoer Mon-Sat during daytime hours only. U-OV operates this route during weekdays, Pouw Vervoer on Saturdays.
70 Amersfoort Station - Soest Zuid - Soest Overhees - Soestdijk Noord - Hooge Vuursche - Hilversum Station Syntus Utrecht; a few runs are operated by Pouw Vervoer and Van Kooten
100 (Hilversum Station -) Blaricum Bijvanck - Huizen - Naarden-Bussum Station Connexxion The route between Hilversum and Blaricum is only served during weekday daytime hours.
104 Hilversum Station - Hilversum-Zuid - Nieuw-Loosdrecht Connexxion
105 Hilversum Station - Kortenhoef - \'s-Graveland - Hilversumse Meent - Naarden-Bussum Station Connexxion
106 (Hilversum Station - Kortenhoef -) Nederhorst den Berg - Weesp Station Connexxion Mon-Sat only. Only runs through from Nederhorst den Berg to Hilversum Mon-Fri during daytime hours.
107 Hilversum Station - Hilversum Mediapark - Bussum - Blaricum Ziekenhuis (Hospital) Connexxion
108 Hilversum Station - Laren - Blaricum Dorp - Huizen Connexxion
109 Hilversum Station - Eemnes - Laren - Blaricum Ziekenhuis (Hospital) - Naarden-Bussum Station Connexxion
121 Hilversum Station - Oud-Loosdrecht - Loenen aan de Vecht - Vinkeveen - Wilnis - Mijdrecht Syntus Utrecht Mon-Sat during daytime hours only. Only runs between Hilversum and Vinkeveen, Groenlandsekade on Saturdays.
320 Hilversum Station - Hilversum Arenapark - Blaricum Bijvanck - Huizen - Blaricum Ziekenhuis (Hospital) - Naarden Gooimeer - Muiden P+R - Amsterdam Amstel Station Connexxion and Pouw Vervoer During weekday daytime hours, Saturday mornings and Sunday evenings, some buses only run between Hilversum and Huizen. During morning rush hours, 4 extra buses run between Hilversum Station and Hilversum Arenapark.
N32 Hilversum Station → Eemnes → Blaricum Bijvanck → Huizen Pouw Vervoer Only runs during Saturday late nights (between midnight and 5 AM).
## Local government {#local_government}
The municipal council of Hilversum consists of 37 seats, which are divided as follows since the last local election of 2022:
- Hart voor Hilversum -- 8 seats
- D66 -- 7 seats
- VVD -- 5 seats
- GroenLinks -- 4 seats
- CDA -- 4 seats
- Democraten Hilversum -- 3 seat
- PvdA -- 2 seats
- SP -- 2 seats
- ChristenUnie -- 1 seat
- Belang van Nederland (BVNL) -- 1 seat
### Government
After the 2022 elections, the municipal government was made up of aldermen from the political parties Hart voor Hilversum, VVD, GroenLinks and CDA. The mayor is Gerhard van den Top.
Hart voor Hilversum, a local party, is the largest group on the council. Originally a part of Leefbaar Hilversum, it separated to form a party called DLPH, which won 1 seat in the 2006 elections. In 2006 leadership was taken over by Léonie Sazias, a TV celebrity. She later changed the party name to Hart voor Hilversum. They won 3 seats in the 2010 elections, 6 in 2014 and 8 in both 2018 and 2022.
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# Hilversum
## Notable residents {#notable_residents}
Notable people born in Hilversum:
### Public service & public thinking {#public_service_public_thinking}
- H. A. Sinclair de Rochemont (1901--1942), a Dutch fascist and later a Nazi collaborator
- Jan van den Brink (1915--2006), a Dutch politician and businessman
- Joop den Uyl (1919--1987), Prime Minister of the Netherlands 1973 to 1977
- Wilhelmus Luijpen (1922--1980), a Dutch philosopher, Catholic priest of the Order of St. Augustine and an existential phenomenologist
- Ineke van Wetering (1934--2011), a Dutch anthropologist who studied witchcraft in Suriname
- Hubert van Es (1941--2009), war journalist in Vietnam
- John Gerretsen (born 1942), politician in Ontario, Canada
- Ernst Bakker (1946--2014), a Dutch politician, Mayor of Hilversum 1998 to 2011
- Olga Fischer (born 1951), a Dutch linguist and academic
- Bartha Knoppers (born 1951), a Canadian lawyer
- Léonie Sazias (1957--2022), Politician and TV presenter
- André Rouvoet (born 1962), a retired Dutch politician
- Janneke Raaijmakers (born 1973), a Dutch historian of the Middle Ages, focus on the Fulda monastery
### The arts {#the_arts}
- Jan Teulings (1905--1989), a Dutch actor
- Emmy Lopes Dias (1919--2005), a Dutch stage, radio, and TV actress and advocate for the right to die
- Pim Jacobs (1934--1996), a Dutch jazz pianist, composer and TV presenter
- Chris Hinze (born 1938), a Dutch former pianist, now jazz and New Age flautist
- Harry van Hoof (born 1943), a Dutch conductor, composer and music arranger
- Harmke Pijpers (born 1946), a Dutch journalist and radio and TV presenter
- Dick Diamonde (1947--2024), a retired Dutch Australian bass guitar player
- Ton Scherpenzeel (born 1952), keyboardist and founder of the Dutch rock band Kayak
- Pim Koopman (1953--2009), drummer of the Dutch progressive rock band, Kayak
- Max Werner (1953--2024), lead singer and drummer of the rock band Kayak
- Erland Van Lidth de Jeude (1953--1987), a Dutch-American actor, opera singer and amateur wrestler
- Arjan Ederveen (born 1956), a Dutch actor, comedian, TV scriptwriter and TV director
- Luc Leestemaker (1957--2012), an American abstract expressionist artist
- Arjen Anthony Lucassen (born 1960), a Dutch singer, songwriter, musician and record producer
- Bert Boeren (born 1962), a Dutch jazz trombonist and educator
- Ruud de Wild (born 1969) a Dutch radio host
- Liza Ferschtman (born 1979), a Dutch classical violinist
- Marieke Blaauw (born 1979), a Dutch animator
- Nicolette Kluijver (born 1984), a Dutch TV presenter and former model
- Rami Ismail (born 1988), a Dutch-Egyptian video games developer
- Lucas & Arthur Jussen, Lucas (born 1993) and Arthur (born 1996) are brothers and form a piano duo.
- Sick Individuals (founded 2010), a Dutch electronic dance music act
### Science & business {#science_business}
- J. W. B. Gunning (1860--1913), Dutch physician and museum director in South Africa
- Joop van Oosterom (1937--2016), Dutch billionaire and chess and billiards sponsor
- Bessel Kok (born 1941), Dutch businessman and chess organiser
- Wim van den Brink (born 1952), Professor of Psychiatry and Addiction at the University of Amsterdam
- Henkjan Honing (born 1959), Professor of Music Cognition at the University of Amsterdam
- John de Mol (born 1955), media tycoon and TV producer
- Pieter Geelen (born 1964), Dutch entrepreneur, co-developed the Mapcode
- Olaf Swantee (born 1966), Dutch businessman, former CEO of EE
### Sport
- de Looper brothers, Henk (1912--2006) and Jan (1914--1987). Dutch field hockey players and bronze medallists at the 1936 Summer Olympics
- Nel van Vliet (1926--2006), a breaststroke swimmer, gold medallist at the 1948 Summer Olympics
- Roel Wiersma (1932--1995), a Dutch footballer, 316 club caps with PSV Eindhoven
- Geertje Wielema (1934--2009), a freestyle and backstroke swimmer, silver medallist at the 1952 Summer Olympics
- Hermsen brothers, Henk (1937--2022)), André (born 1942) and Wim (born 1947), water polo players
- Mary Kok (born 1940), a renowned Dutch swimmer
- Adrie Lasterie (1943--1991), a Dutch swimmer, silver medallist at the 1964 Summer Olympics
- Evert Kroon (1946--2018), water polo goalkeeper, bronze medallist at the 1976 Summer Olympics
- :nl:John van Altena (born 1947), 107 caps, Dutch National Rugby XV
- Ton van Klooster (born 1954), freestyle swimmer and swimming coach, competed at the 1972 Summer Olympics
- Nico Landeweerd (born 1954), water polo player, bronze medallist at the 1976 Summer Olympics
- Andy Hoepelman (born 1955), water polo player, bronze medallist at the 1976 Summer Olympics
- Albert Voorn (born 1956), a Dutch equestrian and silver medallist at the 2000 Summer Olympics
- Alex Boegschoten (born 1956), a former water polo player, bronze medallist at the 1976 Summer Olympics
- Hansje Bunschoten (born 1958--2017), swimmer and TV presenter, competed at the 1972 Summer Olympics
- Ellen Bontje (born 1958), equestrian, team medallist at the 1992 and 2000 Summer Olympics
- Reggie de Jong (born 1964), freestyle swimmer, bronze medallist at the 1980 Summer Olympics
- Jelle Goes (born 1970), a Dutch football manager
- Pieta van Dishoeck (born 1972), a retired rower, won two medals at the 2000 Summer Olympics
- Davy Klaassen (born 1993), a Dutch professional footballer with 180 club caps
## Gallery
<File:Hilversum> centrum A.jpg\|Hilversum city centre <File:Beeld-en-Geluid-Hay-Kranen-09.JPG%7CSound> and Vision (*Nederlands Instituut voor Beeld en Geluid*) <File:Hilversum> Noordse Bosje A.jpg\|Shopping district Noordse Bosje <File:DJI00501.jpg%7CMedia> Park, Hilversum <File:City> Hall, Media Park, Hilversum, North Holland
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# History of the Internet
The history of the Internet originated in the efforts of scientists and engineers to build and interconnect computer networks. The Internet Protocol Suite, the set of rules used to communicate between networks and devices on the Internet, arose from research and development in the United States and involved international collaboration, particularly with researchers in the United Kingdom and France.
Computer science was an emerging discipline in the late 1950s that began to consider time-sharing between computer users, and later, the possibility of achieving this over wide area networks. J. C. R. Licklider developed the idea of a universal network at the Information Processing Techniques Office (IPTO) of the United States Department of Defense (DoD) Advanced Research Projects Agency (ARPA). Independently, Paul Baran at the RAND Corporation proposed a distributed network based on data in message blocks in the early 1960s, and Donald Davies conceived of packet switching in 1965 at the National Physical Laboratory (NPL), proposing a national commercial data network in the United Kingdom.
ARPA awarded contracts in 1969 for the development of the ARPANET project, directed by Robert Taylor and managed by Lawrence Roberts. ARPANET adopted the packet switching technology proposed by Davies and Baran. The network of Interface Message Processors (IMPs) was built by a team at Bolt, Beranek, and Newman, with the design and specification led by Bob Kahn. The host-to-host protocol was specified by a group of graduate students at UCLA, led by Steve Crocker, along with Jon Postel and others. The ARPANET expanded rapidly across the United States with connections to the United Kingdom and Norway.
Several early packet-switched networks emerged in the 1970s which researched and provided data networking. Louis Pouzin and Hubert Zimmermann pioneered a simplified end-to-end approach to internetworking at the IRIA. Peter Kirstein put internetworking into practice at University College London in 1973. Bob Metcalfe developed the theory behind Ethernet and the PARC Universal Packet. ARPA initiatives and the International Network Working Group developed and refined ideas for internetworking, in which multiple separate networks could be joined into a *network of networks*. Vint Cerf, now at Stanford University, and Bob Kahn, now at DARPA, published their research on internetworking in 1974. Through the Internet Experiment Note series and later RFCs this evolved into the Transmission Control Protocol (TCP) and Internet Protocol (IP), two protocols of the Internet protocol suite. The design included concepts pioneered in the French CYCLADES project directed by Louis Pouzin. The development of packet switching networks was underpinned by mathematical work in the 1970s by Leonard Kleinrock at UCLA.`{{Internet history timeline}}`{=mediawiki}In the late 1970s, national and international public data networks emerged based on the X.25 protocol, designed by Rémi Després and others. In the United States, the National Science Foundation (NSF) funded national supercomputing centers at several universities in the United States, and provided interconnectivity in 1986 with the NSFNET project, thus creating network access to these supercomputer sites for research and academic organizations in the United States. International connections to NSFNET, the emergence of architecture such as the Domain Name System, and the adoption of TCP/IP on existing networks in the United States and around the world marked the beginnings of the Internet. Commercial Internet service providers (ISPs) emerged in 1989 in the United States and Australia. Limited private connections to parts of the Internet by officially commercial entities emerged in several American cities by late 1989 and 1990. The optical backbone of the NSFNET was decommissioned in 1995, removing the last restrictions on the use of the Internet to carry commercial traffic, as traffic transitioned to optical networks managed by Sprint, MCI and AT&T in the United States.
Research at CERN in Switzerland by the British computer scientist Tim Berners-Lee in 1989--90 resulted in the World Wide Web, linking hypertext documents into an information system, accessible from any node on the network. The dramatic expansion of the capacity of the Internet, enabled by the advent of wave division multiplexing (WDM) and the rollout of fiber optic cables in the mid-1990s, had a revolutionary impact on culture, commerce, and technology. This made possible the rise of near-instant communication by electronic mail, instant messaging, voice over Internet Protocol (VoIP) telephone calls, video chat, and the World Wide Web with its discussion forums, blogs, social networking services, and online shopping sites. Increasing amounts of data are transmitted at higher and higher speeds over fiber-optic networks operating at 1 Gbit/s, 10 Gbit/s, and 800 Gbit/s by 2019. The Internet\'s takeover of the global communication landscape was rapid in historical terms: it only communicated 1% of the information flowing through two-way telecommunications networks in the year 1993, 51% by 2000, and more than 97% of the telecommunicated information by 2007. The Internet continues to grow, driven by ever greater amounts of online information, commerce, entertainment, and social networking services. However, the future of the global network may be shaped by regional differences.
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# History of the Internet
## Foundations
### Precursors
#### Telegraphy
: The practice of transmitting messages between two different places through an electromagnetic medium dates back to the electrical telegraph in the late 19th century, which was the first fully digital communication system. Radiotelegraphy began to be used commercially in the early 20th century. Telex became an operational teleprinter service in the 1930s. Such systems were limited to point-to-point communication between two end devices.
#### Information theory {#information_theory}
: Fundamental theoretical work in telecommunications technology was developed by Harry Nyquist and Ralph Hartley in the 1920s. Information theory, as enunciated by Claude Shannon in 1948, provided a firm theoretical underpinning to understand the trade-offs between signal-to-noise ratio, bandwidth, and error-free transmission in the presence of noise.
#### Computers and modems {#computers_and_modems}
: Early fixed-program computers in the 1940s were operated manually by entering small programs via switches in order to load and run a series of programs. As transistor technology evolved in the 1950s, central processing units and user terminals came into use by 1955. The mainframe computer model was devised, and modems, such as the Bell 101, allowed digital data to be transmitted over regular unconditioned telephone lines at low speeds by the late 1950s. These technologies made it possible to exchange data between remote computers. However, a fixed-line link was still necessary; the point-to-point communication model did not allow for direct communication between any two arbitrary systems. In addition, the applications were specific and not general purpose. Examples included SAGE (1958) and SABRE (1960).
#### Time-sharing {#time_sharing}
: Christopher Strachey, who became Oxford University\'s first Professor of Computation, filed a patent application in the United Kingdom for time-sharing in February 1959. In June that year, he gave a paper \"Time Sharing in Large Fast Computers\" at the UNESCO Information Processing Conference in Paris where he passed the concept on to J. C. R. Licklider. Licklider, a vice president at Bolt Beranek and Newman, Inc. (BBN), promoted the idea of time-sharing as an alternative to batch processing. John McCarthy, at MIT, wrote a memo in 1959 that broadened the concept of time sharing to encompass multiple interactive user sessions, which resulted in the Compatible Time-Sharing System (CTSS) implemented at MIT. Other multi-user mainframe systems developed, such as PLATO at the University of Illinois Chicago. In the early 1960, the Advanced Research Projects Agency (ARPA) of the United States Department of Defense funded further research into time-sharing at MIT through Project MAC.
### Inspiration
J. C. R. Licklider, while working at BBN, proposed a computer network in his March 1960 paper *Man-Computer Symbiosis*:
In August 1962, Licklider and Welden Clark published the paper \"On-Line Man-Computer Communication\" which was one of the first descriptions of a networked future.
In October 1962, Licklider was hired by Jack Ruina as director of the newly established Information Processing Techniques Office (IPTO) within ARPA, with a mandate to interconnect the United States Department of Defense\'s main computers at Cheyenne Mountain, the Pentagon, and SAC HQ. There he formed an informal group within DARPA to further computer research. He began by writing memos in 1963 describing a distributed network to the IPTO staff, whom he called \"Members and Affiliates of the Intergalactic Computer Network\".
Although he left the IPTO in 1964, five years before the ARPANET went live, it was his vision of universal networking that provided the impetus for one of his successors, Robert Taylor, to initiate the ARPANET development. Licklider later returned to lead the IPTO in 1973 for two years.
### Packet switching {#packet_switching}
*Main article: Packet switching*
The infrastructure for telephone systems at the time was based on circuit switching, which requires pre-allocation of a dedicated communication line for the duration of the call. Telegram services had developed store and forward telecommunication techniques. Western Union\'s Automatic Telegraph Switching System Plan 55-A was based on message switching. The U.S. military\'s AUTODIN network became operational in 1962. These systems, like SAGE and SBRE, still required rigid routing structures that were prone to single point of failure.
The technology was considered vulnerable for strategic and military use because there were no alternative paths for the communication in case of a broken link. In the early 1960s, Paul Baran of the RAND Corporation produced a study of survivable networks for the U.S. military in the event of nuclear war. Information would be transmitted across a \"distributed\" network, divided into what he called \"message blocks\". Baran\'s design was not implemented.
In addition to being prone to a single point of failure, existing telegraphic techniques were inefficient and inflexible. Beginning in 1965 Donald Davies, at the National Physical Laboratory in the United Kingdom, independently developed a more advanced proposal of the concept, designed for high-speed computer networking, which he called packet switching, the term that would ultimately be adopted.
Packet switching is a technique for transmitting computer data by splitting it into very short, standardized chunks, attaching routing information to each of these chunks, and transmitting them independently through a computer network. It provides better bandwidth utilization than traditional circuit-switching used for telephony, and enables the connection of computers with different transmission and receive rates. It is a distinct concept to message switching.
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# History of the Internet
## Networks that led to the Internet {#networks_that_led_to_the_internet}
### NPL network {#npl_network}
Following discussions with J. C. R. Licklider in 1965, Donald Davies became interested in data communications for computer networks. Later that year, at the National Physical Laboratory (NPL) in the United Kingdom, Davies designed and proposed a national commercial data network based on packet switching. The following year, he described the use of \"switching nodes\" to act as routers in a digital communication network. The proposal was not taken up nationally but he produced a design for a local network to serve the needs of the NPL and prove the feasibility of packet switching using high-speed data transmission. To deal with packet permutations (due to dynamically updated route preferences) and to datagram losses (unavoidable when fast sources send to a slow destinations), he assumed that \"all users of the network will provide themselves with some kind of error control\", thus inventing what came to be known as the end-to-end principle. In 1967, he and his team were the first to use the term \'protocol\' in a modern data-commutation context.
In 1968, Davies began building the Mark I packet-switched network to meet the needs of his multidisciplinary laboratory and prove the technology under operational conditions. The network\'s development was described at a 1968 conference. Elements of the network became operational in early 1969, the first implementation of packet switching, and the NPL network was the first to use high-speed links. Many other packet switching networks built in the 1970s were similar \"in nearly all respects\" to Davies\' original 1965 design. The Mark II version which operated from 1973 used a layered protocol architecture. In 1977, there were roughly 30 computers, 30 peripherals and 100 VDU terminals all able to interact through the NPL Network. The NPL team carried out simulation work on wide-area packet networks, including datagrams and congestion; and research into internetworking and secure communications. The network was replaced in 1986.
### ARPANET
Robert Taylor was promoted to the head of the Information Processing Techniques Office (IPTO) at Advanced Research Projects Agency (ARPA) in 1966. He intended to realize Licklider\'s ideas of an interconnected networking system. As part of the IPTO\'s role, three network terminals had been installed: one for System Development Corporation in Santa Monica, one for Project Genie at University of California, Berkeley, and one for the Compatible Time-Sharing System project at Massachusetts Institute of Technology (MIT). Taylor\'s identified need for networking became obvious from the waste of resources apparent to him.
Bringing in Larry Roberts from MIT in January 1967, he initiated a project to build such a network. Roberts and Thomas Merrill had been researching computer time-sharing over wide area networks (WANs). Wide area networks emerged during the late 1950s and became established during the 1960s. At the first ACM Symposium on Operating Systems Principles in October 1967, Roberts presented a proposal for the \"ARPA net\", based on Wesley Clark\'s idea to use Interface Message Processors (IMP) to create a message switching network. At the conference, Roger Scantlebury presented Donald Davies\' work on a hierarchical digital communications network using packet switching and referenced the work of Paul Baran at RAND. Roberts incorporated the packet switching and routing concepts of Davies and Baran into the ARPANET design and upgraded the proposed communications speed from 2.4 kbit/s to 50 kbit/s.
ARPA awarded the contract to build the network to Bolt Beranek & Newman. The \"IMP guys\", led by Frank Heart and Bob Kahn, developed the routing, flow control, software design and network control. The first ARPANET link was established between the Network Measurement Center at the University of California, Los Angeles (UCLA) Henry Samueli School of Engineering and Applied Science directed by Leonard Kleinrock, and the NLS system at Stanford Research Institute (SRI) directed by Douglas Engelbart in Menlo Park, California at 22:30 hours on October 29, 1969.
By December 1969, a four-node network was connected by adding the Culler-Fried Interactive Mathematics Center at the University of California, Santa Barbara followed by the University of Utah Graphics Department. In the same year, Taylor helped fund ALOHAnet, a system designed by professor Norman Abramson and others at the University of Hawaiʻi at Mānoa that transmitted data by radio between seven computers on four islands on Hawaii.
Steve Crocker formed the \"Network Working Group\" in 1969 at UCLA. Working with Jon Postel and others, he initiated and managed the Request for Comments (RFC) process, which is still used today for proposing and distributing contributions. RFC 1, entitled \"Host Software\", was written by Steve Crocker and published on April 7, 1969. The protocol for establishing links between network sites in the ARPANET, the Network Control Program (NCP), was completed in 1970. These early years were documented in the 1972 film Computer Networks: The Heralds of Resource Sharing.
Roberts presented the idea of packet switching to the communication professionals, and faced anger and hostility. Before ARPANET was operating, they argued that the router buffers would quickly run out. After the ARPANET was operating, they argued packet switching would never be economic without the government subsidy. Baran faced the same rejection and thus failed to convince the military into constructing a packet switching network.
Early international collaborations via the ARPANET were sparse. Connections were made in 1973 to the Norwegian Seismic Array (NORSAR), via a satellite link at the Tanum Earth Station in Sweden, and to Peter Kirstein\'s research group at University College London, which provided a gateway to British academic networks, the first international heterogenous resource sharing network. Throughout the 1970s, Leonard Kleinrock developed the mathematical theory to model and measure the performance of packet-switching technology, building on his earlier work on the application of queueing theory to message switching systems. By 1981, the number of hosts had grown to 213. The ARPANET became the technical core of what would become the Internet, and a primary tool in developing the technologies used.
### Merit Network {#merit_network}
The Merit Network was formed in 1966 as the Michigan Educational Research Information Triad to explore computer networking between three of Michigan\'s public universities as a means to help the state\'s educational and economic development. With initial support from the State of Michigan and the National Science Foundation (NSF), the packet-switched network was first demonstrated in December 1971 when an interactive host to host connection was made between the IBM mainframe computer systems at the University of Michigan in Ann Arbor and Wayne State University in Detroit. In October 1972 connections to the CDC mainframe at Michigan State University in East Lansing completed the triad. Over the next several years in addition to host to host interactive connections the network was enhanced to support terminal to host connections, host to host batch connections (remote job submission, remote printing, batch file transfer), interactive file transfer, gateways to the Tymnet and Telenet public data networks, X.25 host attachments, gateways to X.25 data networks, Ethernet attached hosts, and eventually TCP/IP and additional public universities in Michigan join the network. All of this set the stage for Merit\'s role in the NSFNET project starting in the mid-1980s.
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# History of the Internet
## Networks that led to the Internet {#networks_that_led_to_the_internet}
### CYCLADES
The CYCLADES packet switching network was a French research network designed and directed by Louis Pouzin. In 1972, he began planning the network to explore alternatives to the early ARPANET design and to support internetworking research. First demonstrated in 1973, it was the first network to implement the end-to-end principle conceived by Donald Davies and make the hosts responsible for reliable delivery of data, rather than the network itself, using unreliable datagrams. Concepts implemented in this network influenced TCP/IP architecture.
### X.25 and public data networks {#x.25_and_public_data_networks}
Based on international research initiatives, particularly the contributions of Rémi Després, packet switching network standards were developed by the International Telegraph and Telephone Consultative Committee (ITU-T) in the form of X.25 and related standards. X.25 is built on the concept of virtual circuits emulating traditional telephone connections. In 1974, X.25 formed the basis for the SERCnet network between British academic and research sites, which later became JANET, the United Kingdom\'s high-speed national research and education network (NREN). The initial ITU Standard on X.25 was approved in March 1976. Existing networks, such as Telenet in the United States adopted X.25 as well as new public data networks, such as DATAPAC in Canada and TRANSPAC in France. X.25 was supplemented by the X.75 protocol which enabled internetworking between national PTT networks in Europe and commercial networks in North America.
The British Post Office, Western Union International, and Tymnet collaborated to create the first international packet-switched network, referred to as the International Packet Switched Service (IPSS), in 1978. This network grew from Europe and the US to cover Canada, Hong Kong, and Australia by 1981. By the 1990s it provided a worldwide networking infrastructure.
Unlike ARPANET, X.25 was commonly available for business use. Telenet offered its Telemail electronic mail service, which was also targeted to enterprise use rather than the general email system of the ARPANET.
The first public dial-in networks used asynchronous teleprinter (TTY) terminal protocols to reach a concentrator operated in the public network. Some networks, such as Telenet and CompuServe, used X.25 to multiplex the terminal sessions into their packet-switched backbones, while others, such as Tymnet, used proprietary protocols. In 1979, CompuServe became the first service to offer electronic mail capabilities and technical support to personal computer users. The company broke new ground again in 1980 as the first to offer real-time chat with its CB Simulator. Other major dial-in networks were America Online (AOL) and Prodigy that also provided communications, content, and entertainment features. Many bulletin board system (BBS) networks also provided on-line access, such as FidoNet which was popular amongst hobbyist computer users, many of them hackers and amateur radio operators.
### UUCP and Usenet {#uucp_and_usenet}
In 1979, two students at Duke University, Tom Truscott and Jim Ellis, originated the idea of using Bourne shell scripts to transfer news and messages on a serial line UUCP connection with nearby University of North Carolina at Chapel Hill. Following public release of the software in 1980, the mesh of UUCP hosts forwarding on the Usenet news rapidly expanded. UUCPnet, as it would later be named, also created gateways and links between FidoNet and dial-up BBS hosts. UUCP networks spread quickly due to the lower costs involved, ability to use existing leased lines, X.25 links or even ARPANET connections, and the lack of strict use policies compared to later networks like CSNET and BITNET. All connects were local. By 1981 the number of UUCP hosts had grown to 550, nearly doubling to 940 in 1984.
Sublink Network, operating since 1987 and officially founded in Italy in 1989, based its interconnectivity upon UUCP to redistribute mail and news groups messages throughout its Italian nodes (about 100 at the time) owned both by private individuals and small companies. Sublink Network evolved into one of the first examples of Internet technology coming into use through popular diffusion.
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# History of the Internet
## 1973--1989: Merging the networks and creating the Internet {#merging_the_networks_and_creating_the_internet}
### TCP/IP
With so many different networking methods seeking interconnection, a method was needed to unify them. Louis Pouzin initiated the CYCLADES project in 1972, building on the work of Donald Davies and the ARPANET. An International Network Working Group formed in 1972; active members included Vint Cerf from Stanford University, Alex McKenzie from BBN, Donald Davies and Roger Scantlebury from NPL, and Louis Pouzin and Hubert Zimmermann from IRIA. Pouzin coined the term *catenet* for concatenated network. Bob Metcalfe at Xerox PARC outlined the idea of Ethernet and PARC Universal Packet (PUP) for internetworking. Bob Kahn, now at DARPA, recruited Vint Cerf to work with him on the problem. By 1973, these groups had worked out a fundamental reformulation, in which the differences between network protocols were hidden by using a common internetworking protocol. Instead of the network being responsible for reliability, as in the ARPANET, the hosts became responsible.
Cerf and Kahn published their ideas in May 1974, which incorporated concepts implemented by Louis Pouzin and Hubert Zimmermann in the CYCLADES network. The specification of the resulting protocol, the Transmission Control Program, was published as `{{IETF RFC|675}}`{=mediawiki} by the Network Working Group in December 1974. It contains the first attested use of the term *internet*, as a shorthand for internetwork. This software was monolithic in design using two simplex communication channels for each user session.
With the role of the network reduced to a core of functionality, it became possible to exchange traffic with other networks independently from their detailed characteristics, thereby solving the fundamental problems of internetworking. DARPA agreed to fund the development of prototype software. Testing began in 1975 through concurrent implementations at Stanford, BBN and University College London (UCL). After several years of work, the first demonstration of a gateway between the Packet Radio network (PRNET) in the SF Bay area and the ARPANET was conducted by the Stanford Research Institute. On November 22, 1977, a three network demonstration was conducted including the ARPANET, the SRI\'s Packet Radio Van on the Packet Radio Network and the Atlantic Packet Satellite Network (SATNET) including a node at UCL.
The software was redesigned as a modular protocol stack, using full-duplex channels; between 1976 and 1977, Yogen Dalal and Robert Metcalfe among others, proposed separating TCP\'s routing and transmission control functions into two discrete layers, which led to the splitting of the Transmission Control Program into the Transmission Control Protocol (TCP) and the Internet Protocol (IP) in version 3 in 1978. Version 4 was described in IETF publication RFC 791 (September 1981), 792 and 793. It was installed on SATNET in 1982 and the ARPANET in January 1983 after the DoD made it standard for all military computer networking. This resulted in a networking model that became known informally as TCP/IP. It was also referred to as the Department of Defense (DoD) model or DARPA model. Cerf credits his graduate students Yogen Dalal, Carl Sunshine, Judy Estrin, Richard A. Karp, and Gérard Le Lann with important work on the design and testing. DARPA sponsored or encouraged the development of TCP/IP implementations for many operating systems.
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# History of the Internet
## 1973--1989: Merging the networks and creating the Internet {#merging_the_networks_and_creating_the_internet}
### From ARPANET to NSFNET {#from_arpanet_to_nsfnet}
After the ARPANET had been up and running for several years, ARPA looked for another agency to hand off the network to; ARPA\'s primary mission was funding cutting-edge research and development, not running a communications utility. In July 1975, the network was turned over to the Defense Communications Agency, also part of the Department of Defense. In 1983, the U.S. military portion of the ARPANET was broken off as a separate network, the MILNET. MILNET subsequently became the unclassified but military-only NIPRNET, in parallel with the SECRET-level SIPRNET and JWICS for TOP SECRET and above. NIPRNET does have controlled security gateways to the public Internet.
The networks based on the ARPANET were government funded and therefore restricted to noncommercial uses such as research; unrelated commercial use was strictly forbidden. This initially restricted connections to military sites and universities. During the 1980s, the connections expanded to more educational institutions, and a growing number of companies such as Digital Equipment Corporation and Hewlett-Packard, which were participating in research projects or providing services to those who were. Data transmission speeds depended upon the type of connection, the slowest being analog telephone lines and the fastest using optical networking technology.
Several other branches of the U.S. government, the National Aeronautics and Space Administration (NASA), the National Science Foundation (NSF), and the Department of Energy (DOE) became heavily involved in Internet research and started development of a successor to ARPANET. In the mid-1980s, all three of these branches developed the first Wide Area Networks based on TCP/IP. NASA developed the NASA Science Network, NSF developed CSNET and DOE evolved the Energy Sciences Network or ESNet.
NASA developed the TCP/IP based NASA Science Network (NSN) in the mid-1980s, connecting space scientists to data and information stored anywhere in the world. In 1989, the DECnet-based Space Physics Analysis Network (SPAN) and the TCP/IP-based NASA Science Network (NSN) were brought together at NASA Ames Research Center creating the first multiprotocol wide area network called the NASA Science Internet, or NSI. NSI was established to provide a totally integrated communications infrastructure to the NASA scientific community for the advancement of earth, space and life sciences. As a high-speed, multiprotocol, international network, NSI provided connectivity to over 20,000 scientists across all seven continents.
In 1981, NSF supported the development of the Computer Science Network (CSNET). CSNET connected with ARPANET using TCP/IP, and ran TCP/IP over X.25, but it also supported departments without sophisticated network connections, using automated dial-up mail exchange. CSNET played a central role in popularizing the Internet outside the ARPANET.
In 1986, the NSF created NSFNET, a 56 kbit/s backbone to support the NSF-sponsored supercomputing centers. The NSFNET also provided support for the creation of regional research and education networks in the United States, and for the connection of university and college campus networks to the regional networks. The use of NSFNET and the regional networks was not limited to supercomputer users and the 56 kbit/s network quickly became overloaded. NSFNET was upgraded to 1.5 Mbit/s in 1988 under a cooperative agreement with the Merit Network in partnership with IBM, MCI, and the State of Michigan. The existence of NSFNET and the creation of Federal Internet Exchanges (FIXes) allowed the ARPANET to be decommissioned in 1990.
NSFNET was expanded and upgraded to dedicated fiber, optical lasers and optical amplifier systems capable of delivering T3 start up speeds or 45 Mbit/s in 1991. However, the T3 transition by MCI took longer than expected, allowing Sprint to establish a coast-to-coast long-distance commercial Internet service. When NSFNET was decommissioned in 1995, its optical networking backbones were handed off to several commercial Internet service providers, including MCI, PSI Net and Sprint. As a result, when the handoff was complete, Sprint and its Washington DC Network Access Points began to carry Internet traffic, and by 1996, Sprint was the world\'s largest carrier of Internet traffic.
The research and academic community continues to develop and use advanced networks such as Internet2 in the United States and JANET in the United Kingdom.
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# History of the Internet
## 1973--1989: Merging the networks and creating the Internet {#merging_the_networks_and_creating_the_internet}
### Transition towards the Internet {#transition_towards_the_internet}
The term \"internet\" was reflected in the first RFC published on the TCP protocol (RFC 675: Internet Transmission Control Program, December 1974) as a short form of *internetworking*, when the two terms were used interchangeably. In general, an internet was a collection of networks linked by a common protocol. In the time period when the ARPANET was connected to the newly formed NSFNET project in the late 1980s, the term was used as the name of the network, Internet, being the large and global TCP/IP network.
Opening the Internet and the fiber optic backbone to corporate and consumers increased demand for network capacity. The expense and delay of laying new fiber led providers to test a fiber bandwidth expansion alternative that had been pioneered in the late 1970s by Optelecom using \"interactions between light and matter, such as lasers and optical devices used for optical amplification and wave mixing\". This technology became known as wave division multiplexing (WDM). Bell Labs deployed a 4-channel WDM system in 1995. To develop a mass capacity (dense) WDM system, Optelecom and its former head of Light Systems Research, David R. Huber formed a new venture, Ciena Corp., that deployed the world\'s first dense WDM system on the Sprint fiber network in June 1996. This was referred to as the real start of optical networking.
As interest in networking grew by needs of collaboration, exchange of data, and access of remote computing resources, the Internet technologies spread throughout the rest of the world. The hardware-agnostic approach in TCP/IP supported the use of existing network infrastructure, such as the International Packet Switched Service (IPSS) X.25 network, to carry Internet traffic.
Many sites unable to link directly to the Internet created simple gateways for the transfer of electronic mail, the most important application of the time. Sites with only intermittent connections used UUCP or FidoNet and relied on the gateways between these networks and the Internet. Some gateway services went beyond simple mail peering, such as allowing access to File Transfer Protocol (FTP) sites via UUCP or mail.
Finally, routing technologies were developed for the Internet to remove the remaining centralized routing aspects. The Exterior Gateway Protocol (EGP) was replaced by a new protocol, the Border Gateway Protocol (BGP). This provided a meshed topology for the Internet and reduced the centric architecture which ARPANET had emphasized. In 1994, Classless Inter-Domain Routing (CIDR) was introduced to support better conservation of address space which allowed use of route aggregation to decrease the size of routing tables.
### Optical networking {#optical_networking}
The MOS transistor underpinned the rapid growth of telecommunication bandwidth over the second half of the 20th century. To address the need for transmission capacity beyond that provided by radio, satellite and analog copper telephone lines, engineers developed optical communications systems based on fiber optic cables powered by lasers and optical amplifier techniques.
The concept of lasing arose from a 1917 paper by Albert Einstein, \"On the Quantum Theory of Radiation\". Einstein expanded upon a conversation with Max Planck on how atoms absorb and emit light, part of a thought process that, with input from Erwin Schrödinger, Werner Heisenberg and others, gave rise to quantum mechanics. Specifically, in his quantum theory, Einstein mathematically determined that light could be generated not only by spontaneous emission, such as the light emitted by an incandescent light or the Sun, but also by stimulated emission.
Forty years later, on November 13, 1957, Columbia University physics student Gordon Gould first realized how to make light by stimulated emission through a process of optical amplification. He coined the term LASER for this technology---Light Amplification by Stimulated Emission of Radiation. Using Gould\'s light amplification method (patented as \"Optically Pumped Laser Amplifier\"), Theodore Maiman made the first working laser on May 16, 1960.
Gould co-founded Optelecom in 1973 to commercialize his inventions in optical fiber telecommunications, just as Corning Glass was producing the first commercial fiber optic cable in small quantities. Optelecom configured its own fiber lasers and optical amplifiers into the first commercial optical communication systems which it delivered to Chevron and the US Army Missile Defense. Three years later, GTE deployed the first optical telephone system in 1977 in Long Beach, California. By the early 1980s, optical networks powered by lasers, LED and optical amplifier equipment supplied by Bell Labs, NTT and Perelli`{{clarify|reason=Pirelli is a tyre company. Were they really involved in telecoms? If so, why is this spelling retained?|date=February 2025}}`{=mediawiki} were used by select universities and long-distance telephone providers.
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# History of the Internet
## 1973--1989: Merging the networks and creating the Internet {#merging_the_networks_and_creating_the_internet}
### TCP/IP goes global (1980s) {#tcpip_goes_global_1980s}
#### SATNET, CERN and the European Internet {#satnet_cern_and_the_european_internet}
In 1982, Norway (NORSAR/NDRE) and Peter Kirstein\'s research group at University College London (UCL) left the ARPANET and reconnected using TCP/IP over SATNET. There were 40 British research groups using UCL\'s link to ARPANET in 1975; by 1984 there was a user population of about 150 people on both sides of the Atlantic.
Between 1984 and 1988, CERN began installation and operation of TCP/IP to interconnect its major internal computer systems, workstations, PCs, and an accelerator control system. CERN continued to operate a limited self-developed system (CERNET) internally and several incompatible (typically proprietary) network protocols externally. There was considerable resistance in Europe towards more widespread use of TCP/IP, and the CERN TCP/IP intranets remained isolated from the Internet until 1989, when a transatlantic connection to Cornell University was established.
The Computer Science Network (CSNET) began operation in 1981 to provide networking connections to institutions that could not connect directly to ARPANET. Its first international connection was to Israel in 1984. Soon after, connections were established to computer science departments in Canada, France, and Germany.
In 1988, the first international connections to NSFNET was established by France\'s INRIA, and Piet Beertema at the Centrum Wiskunde & Informatica (CWI) in the Netherlands. Daniel Karrenberg, from CWI, visited Ben Segal, CERN\'s TCP/IP coordinator, looking for advice about the transition of EUnet, the European side of the UUCP Usenet network (much of which ran over X.25 links), over to TCP/IP. The previous year, Segal had met with Len Bosack from the then still small company Cisco about purchasing some TCP/IP routers for CERN, and Segal was able to give Karrenberg advice and forward him on to Cisco for the appropriate hardware. This expanded the European portion of the Internet across the existing UUCP networks. The NORDUnet connection to NSFNET was in place soon after, providing open access for university students in Denmark, Finland, Iceland, Norway, and Sweden.
In January 1989, CERN opened its first external TCP/IP connections. This coincided with the creation of Réseaux IP Européens (RIPE), initially a group of IP network administrators who met regularly to carry out coordination work together. Later, in 1992, RIPE was formally registered as a cooperative in Amsterdam.
The United Kingdom\'s national research and education network (NREN), JANET, began operation in 1984 using the UK\'s Coloured Book protocols and connected to NSFNET in 1989. In 1991, JANET adopted Internet Protocol on the existing network. The same year, Dai Davies introduced Internet technology into the pan-European NREN, EuropaNet, which was built on the X.25 protocol. The European Academic and Research Network (EARN) and RARE adopted IP around the same time, and the European Internet backbone EBONE became operational in 1992.
Nonetheless, for a period in the late 1980s and early 1990s, engineers, organizations and nations were polarized over the issue of which standard, the OSI model or the Internet protocol suite would result in the best and most robust computer networks.
#### The link to the Pacific {#the_link_to_the_pacific}
Japan, which had built the UUCP-based network JUNET in 1984, connected to CSNET, and later to NSFNET in 1989, marking the spread of the Internet to Asia.
South Korea set up a two-node domestic TCP/IP network in 1982, the System Development Network (SDN), adding a third node the following year. SDN was connected to the rest of the world in August 1983 using UUCP (Unix-to-Unix-Copy); connected to CSNET in December 1984; and formally connected to the NSFNET in 1990.
In Australia, ad hoc networking to ARPA and in-between Australian universities formed in the late 1980s, based on various technologies such as X.25, UUCPNet, and via a CSNET. These were limited in their connection to the global networks, due to the cost of making individual international UUCP dial-up or X.25 connections. In 1989, Australian universities joined the push towards using IP protocols to unify their networking infrastructures. AARNet was formed in 1989 by the Australian Vice-Chancellors\' Committee and provided a dedicated IP based network for Australia.
New Zealand adopted the UK\'s Coloured Book protocols as an interim standard and established its first international IP connection to the U.S. in 1989.
#### A \"digital divide\" emerges {#a_digital_divide_emerges}
\[\[<File:InternetPenetrationWorldMap.svg%7Cthumb%7C360px>\|
**Internet users in 2023 as a percentage of a country\'s population**
Source: International Telecommunication Union.\]\] *Main article: Global digital divide, Digital divide*
\[\[<File:FixedBroadbandInternetPenetrationWorldMap.svg%7Cthumb> \|360px \|
**Fixed broadband Internet subscriptions in 2012\
as a percentage of a country\'s population**
Source: International Telecommunication Union.\]\]
\[\[<File:MobileBroadbandInternetPenetrationWorldMap> 2013.svg\|thumb \|360px \|
**Mobile broadband Internet subscriptions in 2012\
as a percentage of a country\'s population**
Source: International Telecommunication Union.\]\]
While developed countries with technological infrastructures were joining the Internet, developing countries began to experience a digital divide separating them from the Internet. On an essentially continental basis, they built organizations for Internet resource administration and to share operational experience, which enabled more transmission facilities to be put into place.
#### Africa
At the beginning of the 1990s, African countries relied upon X.25 IPSS and 2400 baud modem UUCP links for international and internetwork computer communications.
In August 1995, InfoMail Uganda, Ltd., a privately held firm in Kampala now known as InfoCom, and NSN Network Services of Avon, Colorado, sold in 1997 and now known as Clear Channel Satellite, established Africa\'s first native TCP/IP high-speed satellite Internet services. The data connection was originally carried by a C-Band RSCC Russian satellite which connected InfoMail\'s Kampala offices directly to NSN\'s MAE-West point of presence using a private network from NSN\'s leased ground station in New Jersey. InfoCom\'s first satellite connection was just 64 kbit/s, serving a Sun host computer and twelve US Robotics dial-up modems.
In 1996, a USAID funded project, the Leland Initiative, started work on developing full Internet connectivity for the continent. Guinea, Mozambique, Madagascar and Rwanda gained satellite earth stations in 1997, followed by Ivory Coast and Benin in 1998.
Africa is building an Internet infrastructure. AFRINIC, headquartered in Mauritius, manages IP address allocation for the continent. As with other Internet regions, there is an operational forum, the Internet Community of Operational Networking Specialists.
There are many programs to provide high-performance transmission plant, and the western and southern coasts have undersea optical cable. High-speed cables join North Africa and the Horn of Africa to intercontinental cable systems. Undersea cable development is slower for East Africa; the original joint effort between New Partnership for Africa\'s Development (NEPAD) and the East Africa Submarine System (Eassy) has broken off and may become two efforts.
#### Asia and Oceania {#asia_and_oceania}
The Asia Pacific Network Information Centre (APNIC), headquartered in Australia, manages IP address allocation for the continent. APNIC sponsors an operational forum, the Asia-Pacific Regional Internet Conference on Operational Technologies (APRICOT).
In South Korea, VDSL, a last mile technology developed in the 1990s by NextLevel Communications, connected corporate and consumer copper-based telephone lines to the Internet.
The People\'s Republic of China established its first TCP/IP college network, Tsinghua University\'s TUNET in 1991. The PRC went on to make its first global Internet connection in 1994, between the Beijing Electro-Spectrometer Collaboration and Stanford University\'s Linear Accelerator Center. However, China went on to implement its own digital divide by implementing a country-wide content filter.
Japan hosted the annual meeting of the Internet Society, INET\'92, in Kobe. Singapore developed TECHNET in 1990, and Thailand gained a global Internet connection between Chulalongkorn University and UUNET in 1992.
#### Latin America {#latin_america}
As with the other regions, the Latin American and Caribbean Internet Addresses Registry (LACNIC) manages the IP address space and other resources for its area. LACNIC, headquartered in Uruguay, operates DNS root, reverse DNS, and other key services.
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# History of the Internet
## 1990--2003: Rise of the global Internet, Web 1.0 {#rise_of_the_global_internet_web_1.0}
### Development
Initially, as with its predecessor networks, the system that would evolve into the Internet was primarily for government and government body use. Although commercial use was forbidden, the exact definition of commercial use was unclear and subjective. UUCPNet and the X.25 IPSS had no such restrictions, which would eventually see the official barring of UUCPNet use of ARPANET and NSFNET connections.
\[\[<File:Internet> Hosts Count log.svg\|thumb \|360px \|
**Number of Internet hosts worldwide: 1969--2019**
Source: Internet Systems Consortium.\]\] As a result, during the late 1980s, the first Internet service provider (ISP) companies were formed. Companies like PSINet, UUNET, Netcom, and Portal Software were formed to provide service to the regional research networks and provide alternate network access, UUCP-based email and Usenet News to the public. In 1989, MCI Mail became the first commercial email provider to get an experimental gateway to the Internet. The first commercial dialup ISP in the United States was The World, which opened in 1989.
In 1992, the U.S. Congress passed the Scientific and Advanced-Technology Act, `{{usc|42|1862(g)}}`{=mediawiki}, which allowed NSF to support access by the research and education communities to computer networks which were not used exclusively for research and education purposes, thus permitting NSFNET to interconnect with commercial networks. This caused controversy within the research and education community, who were concerned commercial use of the network might lead to an Internet that was less responsive to their needs, and within the community of commercial network providers, who felt that government subsidies were giving an unfair advantage to some organizations.
By 1990, ARPANET\'s goals had been fulfilled and new networking technologies exceeded the original scope and the project came to a close. New network service providers including PSINet, Alternet, CERFNet, ANS CO+RE, and many others were offering network access to commercial customers. NSFNET was no longer the de facto backbone and exchange point of the Internet. The Commercial Internet eXchange (CIX), Metropolitan Area Exchanges (MAEs), and later Network Access Points (NAPs) were becoming the primary interconnections between many networks. The final restrictions on carrying commercial traffic ended on April 30, 1995, when the National Science Foundation ended its sponsorship of the NSFNET Backbone Service. NSF provided initial support for the NAPs and interim support to help the regional research and education networks transition to commercial ISPs. NSF also sponsored the very high speed Backbone Network Service (vBNS) which continued to provide support for the supercomputing centers and research and education in the United States.
An event held on 11 January 1994, *The Superhighway Summit* at UCLA\'s Royce Hall, was the \"first public conference bringing together all of the major industry, government and academic leaders in the field \[and\] also began the national dialogue about the *Information Superhighway* and its implications\".
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# History of the Internet
## 1990--2003: Rise of the global Internet, Web 1.0 {#rise_of_the_global_internet_web_1.0}
### Internet use in wider society {#internet_use_in_wider_society}
The invention of the World Wide Web by Tim Berners-Lee at CERN, as an application on the Internet, brought many social and commercial uses to what was, at the time, a network of networks for academic and research institutions. The Web opened to the public in 1991 and began to enter general use in 1993--4, when websites for everyday use started to become available. During the first decade or so of the public Internet, the immense changes it would eventually enable in the 2000s were still nascent. In terms of providing context for this period, mobile cellular devices (\"smartphones\" and other cellular devices) which today provide near-universal access, were used for business and not a routine household item owned by parents and children worldwide. Social media in the modern sense had yet to come into existence, laptops were bulky and most households did not have computers. Data rates were slow and most people lacked means to video or digitize video; media storage was transitioning slowly from analog tape to digital optical discs (DVD and to an extent still, floppy disc to CD). Enabling technologies used from the early 2000s such as PHP, modern JavaScript and Java, technologies such as AJAX, HTML 4 (and its emphasis on CSS), and various software frameworks, which enabled and simplified speed of web development, largely awaited invention and their eventual widespread adoption.
The Internet was widely used for mailing lists, emails, creating and distributing maps with tools like MapQuest, e-commerce and early popular online shopping (Amazon and eBay for example), online forums and bulletin boards, and personal websites and blogs, and use was growing rapidly, but by more modern standards, the systems used were static and lacked widespread social engagement. It awaited a number of events in the early 2000s to change from a communications technology to gradually develop into a key part of global society\'s infrastructure.
Typical design elements of these \"Web 1.0\" era websites included: Static pages instead of dynamic HTML; content served from filesystems instead of relational databases; pages built using Server Side Includes or CGI instead of a web application written in a dynamic programming language; HTML 3.2-era structures such as frames and tables to create page layouts; online guestbooks; overuse of GIF buttons and similar small graphics promoting particular items; and HTML forms sent via email. (Support for server side scripting was rare on shared servers so the usual feedback mechanism was via email, using mailto forms and their email program.
During the period 1997 to 2001, the first speculative investment bubble related to the Internet took place, in which \"dot-com\" companies (referring to the \".com\" top level domain used by businesses) were propelled to exceedingly high valuations as investors rapidly stoked stock values, followed by a market crash; the first dot-com bubble. However this only temporarily slowed enthusiasm and growth, which quickly recovered and continued to grow.
The history of the World Wide Web up to around 2004 was retrospectively named and described by some as \"Web 1.0\".
### IPv6
In the final stage of IPv4 address exhaustion, the last IPv4 address block was assigned in January 2011 at the level of the regional Internet registries. IPv4 uses 32-bit addresses which limits the address space to 2^32^ addresses, i.e. `{{gaps|4|294|967|296}}`{=mediawiki} addresses. IPv4 is in the process of replacement by IPv6, its successor, which uses 128-bit addresses, providing 2^128^ addresses, i.e. `{{gaps|340|282|366|920|938|463|463|374|607|431|768|211|456}}`{=mediawiki}, a vastly increased address space. The shift to IPv6 is expected to take a long time to complete.
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# History of the Internet
## 2004--present: Web 2.0, global ubiquity, social media {#present_web_2.0_global_ubiquity_social_media}
The rapid technical advances that would propel the Internet into its place as a social system, which has completely transformed the way humans interact with each other, took place during a relatively short period from around 2005 to 2010, coinciding with the point in time in which IoT devices surpassed the number of humans alive at some point in the late 2000s. They included:
- The call to \"Web 2.0\" in 2004 (first suggested in 1999).
- Accelerating adoption and commoditization among households of, and familiarity with, the necessary hardware (such as computers).
- Accelerating storage technology and data access speeds -- hard drives emerged, took over from far smaller, slower floppy discs, and grew from megabytes to gigabytes (and by around 2010, terabytes), RAM from hundreds of kilobytes to gigabytes as typical amounts on a system, and Ethernet, the enabling technology for TCP/IP, moved from common speeds of kilobits to tens of megabits per second, to gigabits per second.
- High speed Internet and wider coverage of data connections, at lower prices, allowing larger traffic rates, more reliable simpler traffic, and traffic from more locations.
- The public\'s accelerating perception of the potential of computers to create new means and approaches to communication, the emergence of social media and websites such as Twitter and Facebook to their later prominence, and global collaborations such as Wikipedia (which existed before but gained prominence as a result).
- The mobile device revolution, particularly with smartphones and tablet computers becoming widespread, which began to provide easy access to the Internet to much of human society of all ages, in their daily lives, and allowed them to share, discuss, and continually update, inquire, and respond.
- Non-volatile RAM rapidly grew in size and reliability, and decreased in price, becoming a commodity capable of enabling high levels of computing activity on these small handheld devices as well as solid-state drives (SSD).
- An emphasis on power efficient processor and device design, rather than purely high processing power; one of the beneficiaries of this was Arm, a British company which had focused since the 1980s on powerful but low cost simple microprocessors. The ARM architecture family rapidly gained dominance in the market for mobile and embedded devices.
### Web 2.0 {#web_2.0}
The term \"Web 2.0\" describes websites that emphasize user-generated content (including user-to-user interaction), usability, and interoperability. It first appeared in a January 1999 article called \"Fragmented Future\" written by Darcy DiNucci, a consultant on electronic information design, where she wrote:
The term resurfaced during 2002--2004, and gained prominence in late 2004 following presentations by Tim O\'Reilly and Dale Dougherty at the first Web 2.0 Conference. In their opening remarks, John Battelle and Tim O\'Reilly outlined their definition of the \"Web as Platform\", where software applications are built upon the Web as opposed to upon the desktop. The unique aspect of this migration, they argued, is that \"customers are building your business for you\".`{{primary source inline|reason=A presentation is not per se [[WP:V|verifiable]]. Cite a report, transcript or recording of it instead|date=February 2025}}`{=mediawiki} They argued that the activities of users generating content (in the form of ideas, text, videos, or pictures) could be \"harnessed\" to create value.
\"Web 2.0\" does not refer to an update to any technical specification, but rather to cumulative changes in the way Web pages are made and used. \"Web 2.0\" describes an approach, in which sites focus substantially upon allowing users to interact and collaborate with each other in a social media dialogue as creators of user-generated content in a virtual community, in contrast to Web sites where people are limited to the passive viewing of content. Examples of Web 2.0 include social networking services, blogs, wikis, folksonomies, video sharing sites, hosted services, Web applications, and mashups. Terry Flew, in his 3rd edition of *New Media*, described what he believed to characterize the differences between Web 1.0 and Web 2.0:
This era saw several household names gain prominence through their community-oriented operation -- YouTube, Twitter, Facebook, Reddit and Wikipedia being some examples.
### Telephone networks convert to VoIP {#telephone_networks_convert_to_voip}
Telephone systems have been slowly adopting voice over IP since 2003. Early experiments proved that voice can be converted to digital packets and sent over the Internet. The packets are collected and converted back to analog voice.
### The mobile revolution {#the_mobile_revolution}
The process of change that generally coincided with Web 2.0 was itself greatly accelerated and transformed only a short time later by the increasing growth in mobile devices. This mobile revolution meant that computers in the form of smartphones became something many people used, took with them everywhere, communicated with, used for photographs and videos they instantly shared or to shop or seek information \"on the move\" -- and used socially, as opposed to items on a desk at home or just used for work.
Location-based services, services using location and other sensor information, and crowdsourcing (frequently but not always location based), became common, with posts tagged by location, or websites and services becoming location aware. Mobile-targeted websites (such as \"m.example.com\" ) became common, designed especially for the new devices used. Netbooks, ultrabooks, widespread 4G and Wi-Fi, and mobile chips capable or running at nearly the power of desktops from not many years before on far lower power usage, became enablers of this stage of Internet development, and the term \"App\" (short for \"Application program\" or \"Program\") became popularized, as did the \"App store\".
This \"mobile revolution\" has allowed for people to have a nearly unlimited amount of information at all times. With the ability to access the internet from cell phones came a change in the way media was consumed. Media consumption statistics show that over half of media consumption between those aged 18 and 34 were using a smartphone.
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# History of the Internet
## 2004--present: Web 2.0, global ubiquity, social media {#present_web_2.0_global_ubiquity_social_media}
### Networking in outer space {#networking_in_outer_space}
The first Internet link into low Earth orbit was established on January 22, 2010, when astronaut T. J. Creamer posted the first unassisted update to his Twitter account from the International Space Station, marking the extension of the Internet into space. (Astronauts at the ISS had used email and Twitter before, but these messages had been relayed to the ground through a NASA data link before being posted by a human proxy.) This personal Web access, which NASA calls the Crew Support LAN, uses the space station\'s high-speed Ku band microwave link. To surf the Web, astronauts can use a station laptop computer to control a desktop computer on Earth, and they can talk to their families and friends on Earth using Voice over IP equipment.
Communication with spacecraft beyond Earth orbit has traditionally been over point-to-point links through the Deep Space Network. Each such data link must be manually scheduled and configured. In the late 1990s NASA and Google began working on a new network protocol, delay-tolerant networking (DTN), which automates this process, allows networking of spaceborne transmission nodes, and takes the fact into account that spacecraft can temporarily lose contact because they move behind the Moon or planets, or because space weather disrupts the connection. Under such conditions, DTN retransmits data packages instead of dropping them, as the standard TCP/IP Internet Protocol does. NASA conducted the first field test of what it calls the \"deep space internet\" in November 2008. Testing of DTN-based communications between the International Space Station and Earth (now termed disruption-tolerant networking) has been ongoing since March 2009, and was scheduled to continue until March 2014.`{{update inline|date=January 2025}}`{=mediawiki}
This network technology is supposed to ultimately enable missions that involve multiple spacecraft where reliable inter-vessel communication might take precedence over vessel-to-Earth downlinks. According to a February 2011 statement by Google\'s Vint Cerf, the so-called \"bundle protocols\" have been uploaded to NASA\'s EPOXI mission spacecraft (which is in orbit around the Sun) and communication with Earth has been tested at a distance of approximately 80 light seconds.
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# History of the Internet
## Internet governance {#internet_governance}
As a globally distributed network of voluntarily interconnected autonomous networks, the Internet operates without a central governing body. Each constituent network chooses the technologies and protocols it deploys from the technical standards that are developed by the Internet Engineering Task Force (IETF). However, successful interoperation of many networks requires certain parameters that must be common throughout the network. For managing such parameters, the Internet Assigned Numbers Authority (IANA) oversees the allocation and assignment of various technical identifiers. In addition, the Internet Corporation for Assigned Names and Numbers (ICANN) provides oversight and coordination for the two principal name spaces in the Internet, the Internet Protocol address space and the Domain Name System.
### NIC, InterNIC, IANA, and ICANN {#nic_internic_iana_and_icann}
The IANA function was originally performed by USC Information Sciences Institute (ISI), and it delegated portions of this responsibility with respect to numeric network and autonomous system identifiers to the Network Information Center (NIC) at Stanford Research Institute (SRI International) in Menlo Park, California. ISI\'s Jonathan Postel managed the IANA, served as RFC Editor and performed other key roles until his death in 1998.
As the early ARPANET grew, hosts were referred to by names, and a HOSTS.TXT file would be distributed from SRI International to each host on the network. As the network grew, this became cumbersome. A technical solution came in the form of the Domain Name System, created by ISI\'s Paul Mockapetris in 1983. The Defense Data Network---Network Information Center (DDN-NIC) at SRI handled all registration services, including the top-level domains (TLDs) of .mil, .gov, .edu, .org, .net, .com and .us, root nameserver administration and Internet number assignments under a United States Department of Defense contract. In 1991, the Defense Information Systems Agency (DISA) awarded the administration and maintenance of DDN-NIC (managed by SRI up until this point) to Government Systems, Inc., who subcontracted it to the small private-sector Network Solutions, Inc.
The increasing cultural diversity of the Internet also posed administrative challenges for centralized management of the IP addresses. In October 1992, the Internet Engineering Task Force (IETF) published RFC 1366, which described the \"growth of the Internet and its increasing globalization\" and set out the basis for an evolution of the IP registry process, based on a regionally distributed registry model. This document stressed the need for a single Internet number registry to exist in each geographical region of the world (which would be of \"continental dimensions\"). Registries would be \"unbiased and widely recognized by network providers and subscribers\" within their region. The RIPE Network Coordination Centre (RIPE NCC) was established as the first RIR in May 1992. The second RIR, the Asia Pacific Network Information Centre (APNIC), was established in Tokyo in 1993, as a pilot project of the Asia Pacific Networking Group.
Since at this point in history most of the growth on the Internet was coming from non-military sources, it was decided that the Department of Defense would no longer fund registration services outside of the .mil TLD. In 1993 the U.S. National Science Foundation, after a competitive bidding process in 1992, created the InterNIC to manage the allocations of addresses and management of the address databases, and awarded the contract to three organizations. Registration Services would be provided by Network Solutions; Directory and Database Services would be provided by AT&T; and Information Services would be provided by General Atomics.
Over time, after consultation with the IANA, the IETF, RIPE NCC, APNIC, and the Federal Networking Council (FNC), the decision was made to separate the management of domain names from the management of IP numbers. Following the examples of RIPE NCC and APNIC, it was recommended that management of IP address space then administered by the InterNIC should be under the control of those that use it, specifically the ISPs, end-user organizations, corporate entities, universities, and individuals. As a result, the American Registry for Internet Numbers (ARIN) was established as in December 1997, as an independent, not-for-profit corporation by direction of the National Science Foundation and became the third Regional Internet Registry.
In 1998, both the IANA and remaining DNS-related InterNIC functions were reorganized under the control of ICANN, a California non-profit corporation contracted by the United States Department of Commerce to manage a number of Internet-related tasks. As these tasks involved technical coordination for two principal Internet name spaces (DNS names and IP addresses) created by the IETF, ICANN also signed a memorandum of understanding with the IAB to define the technical work to be carried out by the Internet Assigned Numbers Authority. The management of Internet address space remained with the regional Internet registries, which collectively were defined as a supporting organization within the ICANN structure. ICANN provides central coordination for the DNS system, including policy coordination for the split registry / registrar system, with competition among registry service providers to serve each top-level-domain and multiple competing registrars offering DNS services to end-users.
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# History of the Internet
## Internet governance {#internet_governance}
### Internet Engineering Task Force {#internet_engineering_task_force}
The Internet Engineering Task Force (IETF) is the largest and most visible of several loosely related ad-hoc groups that provide technical direction for the Internet, including the Internet Architecture Board (IAB), the Internet Engineering Steering Group (IESG), and the Internet Research Task Force (IRTF).
The IETF is a loosely self-organized group of international volunteers who contribute to the engineering and evolution of Internet technologies. It is the principal body engaged in the development of new Internet standard specifications. Much of the work of the IETF is organized into *Working Groups*. Standardization efforts of the Working Groups are often adopted by the Internet community, but the IETF does not control or patrol the Internet.
The IETF grew out of quarterly meetings with U.S. government-funded researchers, starting in January 1986. Non-government representatives were invited by the fourth IETF meeting in October 1986. The concept of Working Groups was introduced at the fifth meeting in February 1987. The seventh meeting in July 1987 was the first meeting with more than one hundred attendees. In 1992, the Internet Society, a professional membership society, was formed and IETF began to operate under it as an independent international standards body. The first IETF meeting outside of the United States was held in Amsterdam, the Netherlands, in July 1993. Today, the IETF meets three times per year and attendance has been as high as ca. 2,000 participants. Typically one in three IETF meetings are held in Europe or Asia. The number of non-US attendees is typically ca. 50%, even at meetings held in the United States.
The IETF is not a legal entity, has no governing board, no members, and no dues. The closest status resembling membership is being on an IETF or Working Group mailing list. IETF volunteers come from all over the world and from many different parts of the Internet community. The IETF works closely with and under the supervision of the Internet Engineering Steering Group (IESG) and the Internet Architecture Board (IAB). The Internet Research Task Force (IRTF) and the Internet Research Steering Group (IRSG), peer activities to the IETF and IESG under the general supervision of the IAB, focus on longer-term research issues.
#### RFCs
RFCs are the main documentation for the work of the IAB, IESG, IETF, and IRTF. Originally intended as requests for comments, RFC 1, \"Host Software\", was written by Steve Crocker at UCLA in April 1969. These technical memos documented aspects of ARPANET development. They were edited by Jon Postel, the first RFC Editor.
RFCs cover a wide range of information from proposed standards, draft standards, full standards, best practices, experimental protocols, history, and other informational topics. RFCs can be written by individuals or informal groups of individuals, but many are the product of a more formal Working Group. Drafts are submitted to the IESG either by individuals or by the Working Group Chair. An RFC Editor, appointed by the IAB, separate from IANA, and working in conjunction with the IESG, receives drafts from the IESG and edits, formats, and publishes them. Once an RFC is published, it is never revised. If the standard it describes changes or its information becomes obsolete, the revised standard or updated information will be re-published as a new RFC that \"obsoletes\" the original.
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# History of the Internet
## Internet governance {#internet_governance}
### The Internet Society {#the_internet_society}
The Internet Society (ISOC) is an international, nonprofit organization founded during 1992 \"to assure the open development, evolution and use of the Internet for the benefit of all people throughout the world\". With offices near Washington, DC, US, and in Geneva, Switzerland, ISOC has a membership base comprising more than 80 organizational and more than 50,000 individual members. Members also form \"chapters\" based on either common geographical location or special interests. There are currently more than 90 chapters around the world.
ISOC provides financial and organizational support to and promotes the work of the standards settings bodies for which it is the organizational home: the Internet Engineering Task Force (IETF), the Internet Architecture Board (IAB), the Internet Engineering Steering Group (IESG), and the Internet Research Task Force (IRTF). ISOC also promotes understanding and appreciation of the Internet model of open, transparent processes and consensus-based decision-making.
### Globalization and Internet governance in the 21st century {#globalization_and_internet_governance_in_the_21st_century}
Since the 1990s, the Internet\'s governance and organization has been of global importance to governments, commerce, civil society, and individuals. The organizations which held control of certain technical aspects of the Internet were the successors of the old ARPANET oversight and the current decision-makers in the day-to-day technical aspects of the network. While recognized as the administrators of certain aspects of the Internet, their roles and their decision-making authority are limited and subject to increasing international scrutiny and increasing objections. These objections have led to the ICANN removing themselves from relationships with first the University of Southern California in 2000, and in September 2009 gaining autonomy from the US government by the ending of its longstanding agreements, although some contractual obligations with the U.S. Department of Commerce continued. Finally, on October 1, 2016, ICANN ended its contract with the United States Department of Commerce National Telecommunications and Information Administration (NTIA), allowing oversight to pass to the global Internet community.
The IETF, with financial and organizational support from the Internet Society, continues to serve as the Internet\'s ad-hoc standards body and issues Request for Comments.
In November 2005, the World Summit on the Information Society, held in Tunis, called for an Internet Governance Forum (IGF) to be convened by United Nations Secretary General. The IGF opened an ongoing, non-binding conversation among stakeholders representing governments, the private sector, civil society, and the technical and academic communities about the future of Internet governance. The first IGF meeting was held in October/November 2006 with follow up meetings annually thereafter. Since WSIS, the term \"Internet governance\" has been broadened beyond narrow technical concerns to include a wider range of Internet-related policy issues.
Tim Berners-Lee, inventor of the web, was becoming concerned about threats to the web\'s future and in November 2009 at the IGF in Washington DC launched the World Wide Web Foundation (WWWF) to campaign to make the web a safe and empowering tool for the good of humanity with access to all. In November 2019 at the IGF in Berlin, Berners-Lee and the WWWF went on to launch the *Contract for the Web*, a campaign initiative to persuade governments, companies and citizens to commit to nine principles to stop \"misuse\" with the warning \"If we don\'t act now - and act together - to prevent the web being misused by those who want to exploit, divide and undermine, we are at risk of squandering\" (its potential for good).
## Politicization of the Internet {#politicization_of_the_internet}
Due to its prominence and immediacy as an effective means of mass communication, the Internet has also become more politicized as it has grown. This has led in turn, to discourses and activities that would once have taken place in other ways, migrating to being mediated by internet.
Examples include political activities such as public protest and canvassing of support and votes, but also:
- The spreading of ideas and opinions;
- Recruitment of followers, and \"coming together\" of members of the public, for ideas, products, and causes;
- Providing and widely distributing and sharing information that might be deemed sensitive or relates to whistleblowing (and efforts by specific countries to prevent this by censorship);
- Criminal activity and terrorism (and resulting law enforcement use, together with its facilitation by mass surveillance);
- Politically motivated fake news.
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# History of the Internet
## Net neutrality {#net_neutrality}
On April 23, 2014, the Federal Communications Commission (FCC) was reported to be considering a new rule that would permit Internet service providers to offer content providers a faster track to send content, thus reversing their earlier net neutrality position. A possible solution to net neutrality concerns may be municipal broadband, according to Professor Susan Crawford, a legal and technology expert at Harvard Law School. On May 15, 2014, the FCC decided to consider two options regarding Internet services: first, permit fast and slow broadband lanes, thereby compromising net neutrality; and second, reclassify broadband as a telecommunication service, thereby preserving net neutrality. On November 10, 2014, President Obama recommended the FCC reclassify broadband Internet service as a telecommunications service in order to preserve net neutrality. On January 16, 2015, Republicans presented legislation, in the form of a U.S. Congress HR discussion draft bill, that makes concessions to net neutrality but prohibits the FCC from accomplishing the goal or enacting any further regulation affecting Internet service providers (ISPs). On January 31, 2015, AP News reported that the FCC will present the notion of applying (\"with some caveats\") Title II (common carrier) of the Communications Act of 1934 to the internet in a vote expected on February 26, 2015. Adoption of this notion would reclassify internet service from one of information to one of telecommunications and, according to Tom Wheeler, chairman of the FCC, ensure net neutrality. The FCC is expected to enforce net neutrality in its vote, according to *The New York Times*.
On February 26, 2015, the FCC ruled in favor of net neutrality by applying Title II (common carrier) of the Communications Act of 1934 and Section 706 of the Telecommunications act of 1996 to the Internet. The FCC chairman, Tom Wheeler, commented, \"This is no more a plan to regulate the Internet than the First Amendment is a plan to regulate free speech. They both stand for the same concept.\"
On March 12, 2015, the FCC released the specific details of the net neutrality rules. On April 13, 2015, the FCC published the final rule on its new \"Net Neutrality\" regulations.
On December 14, 2017, the FCC repealed their March 12, 2015 decision by a 3--2 vote regarding net neutrality rules.
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