open-index/open-wikipedia-markdown huggingface dataset:
Coordinated Universal Time

**Coordinated Universal Time** (or **UTC**) is the standard time system of the world. It is the standard by which the world regulates clocks and time. It is, within about 1 second, mean solar time at 0° longitude. 

The standard before was Greenwich Mean Time (GMT). UTC and GMT are almost the same. In fact, there is no practical difference which would be noticed by ordinary people. 

Some websites, for example Wikipedia, use UTC because it does not make any country look more important than the others. It offers one time for all the Internet (the same time can be used by people all over the world). 

Time zones are often named by how many hours they are different from UTC time. For example, UTC−5 (United States east coast) is 5 hours behind UTC. If the time is 07:00 UTC, the local time is 02:00 in New York (UTC−5) and 10:00 in Moscow (UTC+3).

07:00 UTC is also written more simply as 0700Z (or 07:00Z).

Note that UTC uses the 24-hour clock.  That means there is no 'AM' or 'PM'. For example, 4:00PM would be 16:00 or 1600. UTC also does not use daylight saving time - that way the time stays  the entire year.

When this page loaded, it was **,   ,  in UTC**.

## References
Wall

A **wall** is a vertical dividing surface. It divides space in buildings into rooms or protects buildings. It is usually made of stone or brick. Walls have two main purposes: to support the top part of buildings, and to divide space, giving protection from invasion, escape, and weather.

Before powerful artillery was invented, many cities had protective walls. Since they are not suitable for defense any more, most city walls have been removed.

The term "the Wall" usually referred to the Berlin Wall, built during the Cold War, which fell in 1989, but may also refer to the Pink Floyd album of the same name.

Sealing people behind walls, in the form of immurement has historically been a method of human sacrifice and punishment.

## Retaining wall 
A **retaining wall** is a structure made to hold soil from collapsing. It is made in special areas for any other construction work, such as farming or road making.

Types of retaining wall are:
* Anchored wall
* Cantilever wall
* Gravity wall
* Piling wall

## Main type of walls 
**Load Bearing Wall** is a structural element. It carries the weight of a house from the roof and upper floors, all the way to the foundation. It supports structural members like beams, slab and walls on above floors.

**Non-Load Bearing Wall** doesn't help the structure to stand up and holds up only itself. It doesn't support floor roof loads above. It is a framed structure. Most are interior walls whose purpose is to divide the structure into rooms.

**Partition Wall** separates spaces from buildings. It can be solid, constructed from brick or stone. It is a framed construction. The partition wall is secured to the floor, ceiling, and walls. It is enough strong to carry its own load. It resists impact. It is stable and strong to support wall fixtures. The partition wall works as a sound barrier and it is fire resistant.

**Cavity Wall** A cavity wall or hollow wall consists of two separate walls, called leaves or skins, with a cavity or gap in-between. The two leaves of the cavity wall may be of equal thickness if it a non-load-bearing wall or the internal leaf may be thicker than the external leaf, to meet the structural requirements.

**Veneered Wall** holds up the material. It can be made of brick or stone. The most famous veneered wall is made of brick. The wall is only one wythe thick. It became the norm when building codes began to require insulation in interior walls. It is light weighted. Veneered walls can be built quickly.

## Related pages 
* Fire wall
* Wallpaper
* Great Wall of China

## References
South America

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**South America** is the continent to the south of North America. These two continents are separated by the Panama Canal. There are seven continents which make up the globe, South America being the 4th largest. South America includes 12 countries: Argentina, Bolivia, Brazil, Chile, Colombia, Ecuador, Guyana, Paraguay, Peru, Suriname, Uruguay, and Venezuela.

South America is attached to Central America at the  of Panama. Geographically all of Panama – including the part east of the Panama Canal is usually included in North America alone, among the countries of Central America.

## List of Countries 
## Natural resources 
The soil in Argentina's Pampas is among the best in the world. Brazil's soil is very good for growing coffee. A great number of minerals have been found. Few, however, have been mined. Among those that were mined are iron, manganese, gold, and gemstones. The tropical forests are rich in valuable trees, like mahogany, ebony, and rubber.  Oil is also a resource in some places.

## Wildlife 
South America is home to a large variety of animal life. These include animals such as jaguars, macaws, monkeys, anacondas, llamas, piranhas, toucans, rheas, tapirs, cougars, condors and chinchillas.

## Tourist attractions 
The most popular attractions are:
* Machu Picchu, a historic site in Peru which is a city made of stone and has an over 26 mile marathon.
* The Iguazu Falls, a waterfall on the border between Argentina and Brazil
* The Angel Falls, the world's tallest waterfall, in Venezuela
* Rio de Janeiro in Brazil is a huge city, famous for its carnival, beaches (Copacabana and Ipanema), and 38m statue of Jesus Christ.
* The Patagonia region in Argentina and Chile

## The Amazon rain forest 
The amazon rain forest is a moist grassy land where many wild animals live and contains the amazon river which is the 2nd longest river in the world and has the largest volume of water. The world's longest river is the Nile in Africa. The forest is known as a rain forest as it rains very often but due to the dense surroundings not every droplet reaches the bottom. The Amazon is shared by eight **countries** (Brazil, Bolivia, Peru, Ecuador, Colombia, Venezuela, Guyana and Suriname) and stretches for 6.7 million kilometers2. In the amazon rain forest, hundreds of thousands of trees have been cut down for wood and paper, meaning that the forest is endangered. Unlike the Boreial forest in Canada the trees are not getting replanted. 

## Related pages 
* Latin America
* Americas
* Latin American Literature

## References
Television

A **television set** (also known as a **television receiver** or **televisor** or simply a **television**, **TV set**, **TV receiver** or **TV**) is a machine with a screen or set of lenses. Televisions receive broadcasting signals and change them into pictures and sound. The word "television" comes from the words ***tele*** (*far away*) and ***vision*** (*sight*).

Sometimes a television can look like a box. Older TVs had a large cathode ray tube in a large wooden frame and sat on the floor like furniture. Newer TVs are much lighter and flatter. 

A TV can show pictures from many television networks. Computers and mobile devices also can be used for watching television programs.

The television was invented in the 1920s but the equipment was expensive and the pictures were poor. By the 1950s, these problems had been fixed and TVs became widespread.

At first, all televisions used an antenna (or aerial). This would pick up television programmes from broadcasting stations. A TV station could be many miles or kilometers away, and still be received. TVs can also show movies from VCD and DVD players or VCRs. Cable TV and Satellite television can provide more programs at once than broadcast can. Video game consoles connect to most modern TVs. Some computers can also use a TV as a computer monitor.

All TVs have screens where the picture is viewed. Before the 1950s these were usually "black and white", which made everything look grey, but all modern TVs show colors. Most 20th century screens also had rounded corners. That is because television screens were cathode ray tubes. These are like heavy glass jars with one side bulging out to form the screen.  

Today flat panel displays are the usual kind. These are usually flat rectangles with straight edges. This long rectangle looks more like the shape of a movie theatre screen. This is called widescreen. If a widescreen set was 30&nbsp;cm tall, it would be 53&nbsp;cm wide. For this to work best, TV shows also need to be made in widescreen.  Widescreen sets can still be any size, but they have the same widescreen shape.

The early 21st century is also when digital television transmission became more common than analog television.

## Also see
This section needs expansion.

## References
Tone language

A **tonal language** or **tone language** is a language in which words can differ by tones (like pitches in music) in addition to consonants and vowels.

Many languages, including Mandarin, Cantonese, Vietnamese, Thai, Lao, Hmong, Meitei, Punjabi, Yorùbá, Igbo, Luganda, Ewe, Lingála, Cilubà, and Cherokee are tonal. Other languages, including Indo-European languages such as  English and Hindi, are not considered tonal languages but can use intonation in different ways.

In some languages, pitch accent is important instead. A word's meaning can then change if a different syllable is pronounced with a higher pitch. Examples include Ancient Greek, Swedish, Norwegian, Serbo-Croatian, Lithuanian, and some Asian languages like Japanese.

Some tones may sound alike to people who do not speak a tone language. They are the most difficult part of learning a tone language for those people.

## Example
In Mandarin, the most famous example is "*mā má mǎ mà* (), " which has four different words, which are pronounced in exactly the same way but with four different tones. If numbers identify the tones, they can be written m*a1 ma2 ma3 ma4*, which means "mom hemp horse scold." Some ways of romanization mark each tone by a different spelling; *ma1 ma2 ma3 ma4* in Pinyin would be written *ma mha maa mah* in Gwoyeu Romatzyh. Most use numbers or accent marks (*mā má mǎ mà* in Pinyin). There is a passage called Lion-Eating Poet in the Stone Den (). It has 92 characters, all of which read the same way in Mandarin ("shi") but with different tones.

Mandarin does not have many syllables. The words for "mother," "hemp," "horse," "scold," and a word put at the end of sentences to make it a question are all pronounced "ma:"
*"Mother" is "ma" that is high and level.
*"Hemp" is "ma" that starts low and ends high.
*"Horse" is "ma" that starts fairly high, dips very low, and then goes back up again.
*"Scold" is "ma" that starts high and ends low.
*To make a question, "ma" is added at the end, but it is kept very soft and short and about the same level.

Mandarin has "first tone," "second tone," "third tone," "fourth tone," and "neutral tone." Other Chinese dialects have more tones, with some as many as twelve.

## Tonal markings
Vietnamese and pinyin use accents as the tone marks for the Latin alphabet. Each accent shows an altered sound for the syllable. Most syllables have only one tone marking, but the letters in the syllable can be altered by other markings. Syllables usually form one word in un-hyphenated compound words.

Pinyin may have style differences because it is made to help Westerners. On the other hand, Vietnamese has a national script that always has the same style.

## References
Dollar

A **dollar** is a type of currency. Many countries have named their money *the dollar*, so it is important to say which dollar is being talked about. The symbol for the dollar is a capital letter S, pierced by one or two vertical lines (**$**).

## History 
The dollar is named after the thaler. The thaler was a large silver coin first made in the year 1518. The thaler named after the Joachimsthal (Joachim's valley) mine in Bohemia (*Thal* means valley in German). The later Spanish Peso was the same size and was often called "Spanish dollar" and the similar coin of the Dutch Republic was called “lion dollar”. In the 18th century it became a world currency. Many national currencies were originally Spanish dollars including the ones now called dollar or peso and the Japanese yen and Chinese Renminbi.

## List of dollars
*Australian dollar
*Bahamian dollar
*Barbadian dollar
*Belize dollar
*Brunei dollar
*Canadian dollar
*East Caribbean dollar
*Hong Kong dollar
*Jamaican dollar
* Namibian dollar
*New Zealand dollar
*New Taiwan dollar
*Singapore dollar
*United States dollar
*Zimbabwean dollar
Sky

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The **sky** is the appearance of the atmosphere around the surface of the planet from our point of view. We see many objects that are actually in space such as the Sun, the Moon, and stars because they are in the sky. On a clear day the sky appears blue.

## Physics
At night, it appears from very dark blue to black. The deepness of the blue increases as we look toward the horizon, and up to the point above us. The sky, which is made up of gas molecules, is blue because of the random scattering of sunlight by the molecules.

### Rayleigh scattering
Rayleigh scattering defines the amount of scattering of light rays. Blue light scatters much more than red, which is why the sky appears blue on a clear day. Depending on the time of day, the sky may appear different colors. At sunrise or sunset, the sky may appear red, orange and other colors depending on how low the sun is and how close it is to night. 

Many objects can be seen in the sky. There are objects from space like the Sun, Moon, planets and stars. There are also many weather events seen in the sky. For example, these can be fog, clouds, rain or lightning. Weather is caused by different patterns and temperatures in the atmosphere. Other things that can be seen in the sky are birds, other flying animals, and aircraft.

## Solar System
Other planets have skies too. Because the types of gases in their atmospheres are different, they have different sky colors. For example, the sky on Mars is pink.

## Related pages
* Weather
* Atmosphere
* Atomic physics
* Atmospheric chemistry
* Environmental chemistry

## Other websites
* Day Sky Images 
* Night Sky Images 
* Sky Photo Gallery 
* Why is the sky blue?

## References
Eurasia

**Eurasia** is the combined landmass of Europe and Asia in the northern part of Earth. It has the Atlantic Ocean on its west, and the Pacific Ocean to the east. The Arctic Ocean is to its north, and the Mediterranean and Indian Ocean to its south. It is the largest of the continents. Its name comes from adding the "Eur" from "Europe" to "Asia". It and Africa form a part of the world called "Afro-Eurasia".

Some geographers say Eurasia is one continent, because Europe and Asia are mostly on the same tectonic plate and do not have a sea between them. The Ancient Greeks divided the world they knew into Europe, Asia and Africa. To them, the Aegean Sea was the division between the Balkan Peninsula in Europe and Asia Minor in Asia. North of the Sea of Marmara, the Greeks thought the lands on the western side of the Black Sea was Europe and the eastern side was Asia. The ancient Greeks did not know very much about the lands north of the Black Sea. Since Classical Antiquity, people have talked about Asia and Europe separately, so it is now a tradition to see them as two continents.

Some other continents, which are not completely divided by sea, are joined by a thin strip of land (called an isthmus). An example is North America and South America, which are connected by the Isthmus of Panama. Europe and Asia are not divided by a sea, nor by any isthmus.

Outside of geological definitions, Eurasia also includes the Indian subcontinent and the Arabian Peninsula.

Sometimes Eurasia is divided into West Eurasia and East Eurasia. Here, the dividing line is the Ural Mountains. West Eurasia includes Europe and the Middle East. Historians sometimes add North Africa to West Eurasia, because the Sahara Desert divides North Africa from Sub-Saharan Africa, and it is as difficult to cross as a sea. Also, North Africa is culturally linked to Europe by the Mediterranean Sea.

## List of countries 
* 
* 
* 
*  Geologically in Europe and Asia
*  (EU)
*  Geologically in Europe and Asia
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* 
* 
*  (EU)
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* 
*  (EU)
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* 
* 
*  (EU)
*  (EU) Geologically in Europe and Asia
*  (EU)
*  (EU) Geologically in Europe and North America
*  Geologically in Africa and Asia
*  (EU)
*  (EU)
*  (EU)
*  Geologically in Europe and Asia
*  (EU)
*  (EU)
*  (EU)
*  Geologically in Europe and North America
* 
* 
* 
* 
*  (EU)
* 
*  (EU)
* 
* 
*  Geologically in Europe and Asia
* 
* 
* 
*  (EU)
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* 
*  (EU)
*  (EU)
*  (EU)
* 
* 
*  (EU) Geologically in Europe and Africa
* 
* 
* 
* 
* 
* 
*  (EU)
* 
* 
* 
* 
* 
* 
*  (EU)
*  (EU)
* 
*  (EU)
*  Geologically in Europe and Asia
* 
* 
* 
* 
*  (EU)
*  (EU)
* 
*  (EU)
* 
*  (EU)
* 
* 
* 
* 
* 
*  Geologically in Europe and Asia
* 
* 
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* 
* 
* 
* 
* 

The OECD’s Eurasia activities involve 13 countries extending from the borders of the European Union to the Far East:
* Afghanistan
* Armenia
* Azerbaijan
* Belarus
* Georgia
* Kazakhstan
* Kyrgyzstan
* Mongolia
* Republic of Moldova
* Tajikistan
* Turkmenistan
* Ukraine
* Uzbekistan
* Turkey
North Pole

The **North Pole** is the point that is farthest north on Earth. It is the point on which axis of Earth turns. It is in the Arctic Ocean and it is cold there because the sun does not shine there for about half a year and never rises very high. The ocean around the pole is always very cold and it is covered by a thick sheet of ice. 

There is also a Magnetic North Pole. It is near the physical North Pole. A compass points toward the magnetic North Pole.

There is a star called the North Star (or Polaris) that is always in the sky above the North Pole. People can tell how far north they are by seeing how high the North Star appears in the sky.

## Climate
## Related pages
* South Pole

## References
Alexander Gode

**Alexander Gottfried Friedrich Gode-von Aesch**, or simply **Alexander Gode** (October 30, 1906 – August 10, 1970), was a German-American linguist, and translator. He helped create the auxiliary language Interlingua.
Plural

In linguistics, noun phrases have grammatical number. **Plural** is one kind of grammatical number. In English, **plural** noun phrases are counted as more or less than one (e.g., *32 degrees, no bananas*, *0.5 liters*, *1.2 grams*, *two times*, *three fish*, *20 mothers*). In contrast, a singular noun phrase usually refers to something that you would count as one only (e.g., *one time*, *a glass*, *the sun*, *my mother*, *Jennifer*). Noun phrases that cannot be counted are also singular in English (e.g., *water*, *the meat*, *some space*, etc.).

In many languages, a suffix (word ending) is added to a word to show that the word is plural. In English, the normal plural suffix *i*s *-s* (e.g., *cat* is singular, and *cat**s*** is plural).

## Plurals in English 
There are a number of exceptions:
*Singulars ending in s are usually the same in plural: *species*, *mumps*, *innings* and so on. However, proper nouns ending in 's' take add 'es' in plural: *Jones* becomes *the Joneses*. 
*Compound words add the plural to the noun part: sons-in-law, Lord Mayors, Courts Martial.
*Singulars ending in y become ies in the plural if a consonant is before the suffix: day becomes days, but spy becomes spies. Personal names are again exceptions: the plural of Mary is Marys.
*Singulars ending in f usually changes to ves: dwarf to dwarves, leaf to leaves, and so on.
*Special cases: some plurals just have to be learnt. The plural of *person* is normally *people*, but sometimes *persons* is used.
*Invariant nouns: The common names of animals is often used as both singular and plural. One can say "We shot grouse today" correctly no matter what number were killed. With "fish" there is a choice. The traditional English usage is that the word is used for both singular and plural, but American usage seems to prefer fishes as the plural. With groups of animals, one uses the singular, as in a herd of bison or a shoal of herring. However, if the animals are known as individuals then, for example, we feed the ducks, or stroke our cats. There are other cases where there is no plural at all, as with sheep, salmon, deer. Other general words which add no suffix in plural are *aircraft* and *offspring*. Some look like singular but are always plural, such as *vermin*, *livestock*, *cattle*, *people*.

It is fair to say that most native English-speakers make mistakes in this area, which is one of the more troublesome aspects of English.

## Other languages 
All European languages have plural forms. The suffix that is used in each language is different from the one that is applied to English nouns.

In other languages, such as Chinese, Korean and Japanese, there is usually no plural but not for ending.

## References
Southern Ocean

The **Southern Ocean**, also called the **Antarctic Ocean**, is the ocean around the continent of Antarctica. The fourth-largest sea by area, at 20,327,000&nbsp;km², it has a coastline 17,968&nbsp;km long and is surrounded by the waters of the Atlantic, Pacific, and Indian Oceans.

Since the 1770s, geographers have discussed its limits, but the latitude sixty degrees south is now often accepted. It includes several seas like Cosmonauts, Somov, Commonwealth, and Mowson.

## Other websites 
* Oceanography Image of the Day, from the Woods Hole Oceanographic Institution
* The CIA World Factbook's  entry on the Southern Ocean
* The Fifth Ocean  from Geography.About.com
* NOAA In-situ Ocean Data Viewer  Plot and download ocean observations
* NOAA FAQ about the number of oceans
Corset

A **corset** is a body covering undergarment (clothes worn under others).

It is made in many forms.
*A tight-lacing corset is a common form used today.  
*"Stays" are an old form, which were used from about 1500 to after 1860
*An orthopaedic corset supports the back of an injured person.

## Other websites
Oceania

**Oceania** is a large geographical region in the Pacific Ocean. It is made up of 14 countries in the surrounding area. It is often listed with the continents of the world.

The term "Oceania" does not have one single agreed definition. The widest definition of Oceania includes the entire region between continental Asia, Australasia, and the Americas as well as islands in the Pacific Rim such as the Japanese archipelago, Taiwan, and the Aleutian Islands.

On the other hand, the Oceania ecozone includes all of Micronesia, Fiji (Melanesia) and all of Polynesia, except New Zealand. Sometimes, people use the term 'Oceania' to include only the Polynesian and Melanesian islands in the Pacific Ocean, as separate from Australasia. When Oceania is treated separately from Australia, the region of Oceania is referred to as "Australia and Oceania".

In the United Nations' geographic regions, Oceania includes Australia and the nations of the Pacific from Papua New Guinea east, but not the Malay Archipelago or Indonesian New Guinea.

A smaller usage of Oceania as a continent includes only Australia (including Tasmania), New Guinea, and the islands between them. This part of the world is usually called Australasia instead. For these reasons, it is *not* correct to say that Australasia is part of Oceania, because what is meant by 'Oceania' is not clear. Australasia has an exact definition in biogeography and geology; Australasia includes New Zealand, Australia (including Tasmania), and Melanesia, New Guinea, and the islands just north and east of Australia. All these are south-east of the Bali–Lombok line, also known as the Wallace Line.

## Countries in Oceania
Some listed here are part of a larger State.
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## Languages 
* Bislama in Vanuatu
* Chamorro in Guam and Northern Mariana Islands
* Chinese in Kiribati
* English in Australia, New Zealand, Papua New Guinea, Solomon Islands, Fiji, etc.
* Fijian in Fiji
* French in Vanuatu and France's overseas territories
* Gilbertese in Kiribati
* Hawaiian in Hawaii
* Hindi in Fiji
* Hiri Motu in Papua New Guinea
* Indonesian in South Papua, West Papua, Aru Islands, etc
* Japanese in Bonin Islands
* Malay in Chrismas Island and Cocos (Keeling) Islands
* Maori in Cook Islands
* Marshallese in Marshall Islands
* Nauruan in Nauru
* Niuean in Niue
* Norfuk in Norfolk Island
* Palauan in Palau
* Pidgin in Hawaii
* Pitkern in Pitcairn Islands
* Rapanui in Easter Island
* Rarotongan in Cook Islands
* Samoan in Samoa and American Samoa
* Spanish in Guam, Micronesia, Northern Mariana Islands, Palau, Easter Island, Galapagos Islands and the Juan Fernandez Islands
* Tok Pisin in Papua New Guinea
* Tokelauan in Tokelau
* Tongan in Tonga
* Tuvaluan in Tuvalu

## References
### Notes
Catalan language

The **Catalan language** is a Romance language spoken in Catalonia, Valencian Community, the eastern part of Aragon, the Balearic Islands, a small zone of Murcia (all of them in Spain), Andorra, North Catalonia (in France) and the Italian city of L'Alguer. Together, those places are often called the Catalan Countries.

The language that most similar is Occitan. Catalan also has similarities to other Romance languages, such as Spanish, Italian, French and Portuguese. It came from Vulgar Latin and was first spoken in the in the Eastern Pyrenees in the Middle Ages.

There are about 4 million people who speak Catalan as a first language and about 6 million people as a second language. Catalan is the sixth-most-spoken Romance language and also the most-spoken language that is not an official language in the European Union.

## References
Semiotics

**Semiotics** (or **semiology**) is a theoretical framework for the study of the meaning of language, signs and symbols. It was first developed in the early 20th century, separately, by the Swiss Ferdinand Saussure and Charles Sanders Peirce of the U.S.A. 

Semiotics can be described as both a science and a technique. It is a science because it has its own theories. At the same time, it is a technique because it is a way of studying systems of representation and meaning. The meaning can be intentional, such as a word uttered with a specific meaning. It can also be unintentional, such as a symptom being a sign of a particular medical condition. Signs can communicate through any of the senses: visual, auditory, tactile, olfactory, or gustatory.

## History and terminology 
The importance of signs and signification has been recognized throughout much of the history of philosophy and psychology. The term derives from the Greek: σημειωτικός, romanized: *sēmeiōtikos*, "observant of signs" (from σημεῖον *sēmeion*, "a sign, a mark"). For the ancient Greeks, "signs" occurred in the world of nature, while "symbols" occurred in the world of culture. Famous Greek philosophers Plato and Aristotle explored the relationship between signs and the world.

The general study of signs began in Latin with Augustine. It concluded with the important 1632 *Tractatus de Signis* by John Poinsot. However, it began anew in late modernity with the attempt in 1867 by Charles Sanders Peirce to draw up a "new list of categories." More recently, Umberto Eco, in his *Semiotics and the Philosophy of Language*, has argued that semiotic theories are implicit in the work of most, perhaps all, major thinkers.  

## Parts 
Semiotics is usually divided into three parts:
*Semantics -  What was the meaning of the words or signs that were used?
*Pragmatics - Who said it, who did they say it to, and in what circumstances?
*Syntactics - The formal rules of the language being used.

### Branches 
The major branches of semiotics include:
*Biosemiotics
*Zoosemiotics
*Semiotics of culture

## Other page 
*Atomic semiotics
*Philosophy of language

## References
Color

**Color** (or **colour** in Commonwealth English; see spelling differences) is a property of light.

The following are the most common color names:

* Red
* Orange
* Yellow
* Green
* Cyan
* Blue
* Magenta
* Purple
* Lavender
* Lilac
* White
* Black
* Grey
* Silver

* Pink
* Maroon
* Brown
* Beige
* Tan
* Peach
* Lime
* Olive
* Turquoise
* Teal
* Navy blue
* Indigo
* Violet
* ChartreuseOlo

Primary colors can be mixed to make other colors. Red, yellow, and blue are the three traditional primary colors. The primary colors for television screens and computer monitors are red, green and blue. Printers and paints use magenta, yellow, and cyan as their primary colors; they may also use black. Sometimes this set of colors is simply called red, yellow, and blue.

People who can not see colors or have a distorted sense of color are called color-blind. Most color-blind people are male. 

Colors are sometimes added to food. Food coloring is used to color food, but some foods have natural colorings, like beta carotene.

When something has no color, it is called transparent. An example is air.

The science of color is sometimes called chromatics, colorimetry, or simply color science.

A translucent material is not the same as a colorless material because it can still have a color, such as stained glass.

## Related pages
* Color vision
* List of colors

## References
Ion

An **ion** is an electrically charged atom or molecule (group of atoms). It is "charged" so it will move near electricity. Atoms are made from positively charged protons, negatively charged electrons, and uncharged neutrons. Ions are charged because they have an unequal number of protons and electrons.

Making an ion from an atom or molecule is called *ionization*. Two or more ions can combine to make a chemical compound. The link between the ions is called an ionic bond.

The charge on a proton is chosen as +1 (positively charged). The charge on an electron is opposite to the charge on the proton.  The charge on the electron is -1 (negatively charged). An atom that is ionized makes two parts, one positive, and one negatively charged. For example, a neutral hydrogen atom has one proton and one electron. Ionizing the atom breaks it into two parts: (1) a positively charged hydrogen ion, H+ (2) and a negatively charged electron.

A liquid with ions is called an electrolyte. A gas with lots of ions is called a plasma. When ions move, it is called electricity. For example, in a wire, the metal ions do not move, but the electrons move as electricity. A positive ion and a negative ion will move together. Two ions of the same charge will move apart. When ions move they also make *magnetic fields*.

Many ions are colourless. Elements in the main groups in the periodic Table form colourless ions. Some ions are coloured. The transition metals usually form coloured ions.

## Chemistry
In physics, atomic nuclei that have been completely ionized are called ***charged particles***. These are ones in alpha radiation.
 
Ionization happens by giving atoms high energy. This is done using electrical voltage or by high-energy ionizing radiation or high temperature. 

A **simple ion** is formed from a single atom.

**Polyatomic ions** are formed from a number of atoms. Polyatomic ions usually consist of all non-metal atoms. But sometimes the polyatomic ion can have a metallic atom too.

Positive ions are called **cations**. They are attracted to cathodes (negatively charged electrodes).  (*Cation* is pronounced "cat eye on", not "kay shun".) All simple metal ions are cations.

Negative ions are called **anions**. They are attracted to anodes (positively charged electrodes). All simple non-metal ions (except H+, which is a proton) are anions. 

Transition metals can form more than one simple cation with different charges.

Most ions have a charge of less than 4, but some can have higher charges.

Michael Faraday was the first person to write a theory about ions, in 1830. In his theory, he said what the portions of molecules were like that moved to anions or cations. Svante August Arrhenius showed how this happened. He wrote this in his doctoral dissertation in 1884 (University of Uppsala). The university did not accept his theory at first (he only just passed his degree). But in 1903, he won the Nobel Prize in Chemistry for the same idea.

In Greek *ion* is like the word "go". "Anion" and "cation" mean "up-goer" and "down-goer". "Anode" and "cathode" are "way up" and "way down".

### Common ions
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## References
Cognitive science

**Cognitive science** studies how people make their ideas and what makes thoughts logical. It is often seen as the result of several different scientific fields working together. These fields are psychology (a study of the mind), neuroscience (biological study of the brain), computer science (the creation of programs and computers), and linguistics (the study of language). It does not refer to the sum of all these disciplines. It refers to their intersection on specific problems.
## Other websites
* 
* Cognitive Science Society
* Cognitive Science Movie Index: A broad list of movies showcasing themes in the Cognitive Sciences 
* List of leading thinkers in cognitive science 
* Dr. Carl Stahmer's history page at the University of Santa Barbara
Scurvy

**Scurvy** is a disease (sickness). It is caused by not eating enough vitamin C. But scurvy can be prevented. It has many symptoms. People who have scurvy get spots on their skin, especially on their legs. Their teeth may loosen and/or fall out. They may bleed from the mouth, nose, and gums (mucus membranes). A person with scurvy will look pale and feel sad (see depression). They will not be able to move easily, because their joints hurt.

Scurvy can be easily cured. Oranges and other fruits can restore normal vitamin levels. In the past, sailors more commonly got scurvy due to being unable to access these foods. Fresh fruit could not be kept for long. The main cause of scurvy is lack of fresh fruits and vegetables. It is now uncommon.

## Signs of scurvy
**At first, a person with scurvy may:**
#Not want to eat (loss of appetite)
#Feel sad *(slight depression)*
#Lose weight or not get heavier even though they eat a lot
#Have loose feces (diarrhea)
#Breathe fast (tachypnea)
#Be hot (have a high body temperature or fever)

**A bit later a person with scurvy may:**
#Feel angry (irritability)
#Have pains in the legs (and tenderness)
#Find it hard to move (pseudo paralysis)
#Have swelling of the arms and legs
#Bleed from the mouth, nose and gums

## Causes 
#Not eating enough food that has vitamin C
#Going on a long trip, often at sea, where there is no fresh food
#Not having enough food (famine)
#Breaking down the vitamin C by over-cooking (like boiling fruit juice)

## Treatment
#Eating vitamin C pills or giving it by needle (injection, also known as a shot). The injection almost always cures scurvy in babies.
#Drinking orange juice is another treatment that works in babies. Before vitamin C was discovered this was the only treatment.

When a person gets help for scurvy, they usually get better very quickly. Babies start eating again after one or two days of help. The symptoms get better within seven days.

## Food sources
Eating vitamin C  scurvy. How much vitamin C a person needs changes with his or her age and is different for pregnant and lactating women. The following is the Food and Nutrition Board of the National Academy of Sciences, National Research Council's advice on how much vitamin C to eat every day:

* Infants (babies): 30–40&nbsp;mg 
* Children and adults: 45–60&nbsp;mg 
* Pregnant women: 70&nbsp;mg 
* Mothers breast feeding: 90–95&nbsp;mg

Foods with a lot of vitamin C include the following:

* Citrus fruits (for example: oranges, limes)
* Berries 
* Cantaloupe 
* Broccoli 
* Cauliflower 
* Cabbage 
* Spinach 
* Potatoes 
* Tomatoes
* Strawberries

## References
Theology

**Theology** is the study of one or more religions 
(‘Theo-’ means God in Greek and ’-logy’ is study, which makes it ’God study’ or ’study of God’). Somebody who studies theology is called a theologian. Books or ideas about theology are called theological.

Theology may be studied for many reasons. Some people study theology to better understand their own religion, while other people study theology so that they can compare religions.

The word ‘theology’ was first used to describe the study of God in Christianity but some now use it to describe the study of religion generally, but not everyone agrees that it is right to do so. Some people use the words 'comparative theology' in reference to approaching theology within more than one religion at once.

During the High Middle Ages, it was thought that theology was the highest subject learned in universities. Theology at that time was named "The Queen of the Sciences". There was a plan for young men to study easy subjects and then harder subjects. The easiest subjects were called the Trivium. The next harder subjects were called the Quadrivium. Finally, young men were expected to study theology. This meant that the other subjects existed primarily to help with theological thought.

## Related pages 
*Christian theology

## Other websites
*What is theology? theology.edu
Work

**Work** can mean different things depending on how the word is used.

* Employment
* Labour (economics)
* Work (physics), something that happens when a force is applied to an object and a resulting movement takes place
Argon

**Argon** is a chemical element. Its symbol is argon is **Ar** and its atomic number is 18. It is part of the noble gas group. It is an odorless and tasteless gas. Argon is the third-most abundant gas in the Earth's atmosphere.

The name "argon" is from the Greek word ἀργός meaning "lazy" or "inactive" because it does not react with other chemicals.

## Chemistry 
Argon atoms are found in air. About 1% of the Earth's atmosphere (the air around us) is argon. It is not toxic and it does not burn easily. Not many compounds can be made from Argon. However, some compounds have been formed, like argon fluorohydride (HArF). Argon has a higher density than the gases in the atmosphere as a whole, so if a balloon is filled with argon, it would fall to the ground.  This means it can be used to displace oxygen and nitrogen at the bottom of an enclosed space, so, while non-toxic, it must be handled with care.

## History 
Argon was first removed from air in 1894 by Lord Rayleigh and Sir William Ramsay at University College London by removing oxygen, carbon dioxide, water, and nitrogen from a sample of clean air.
## Isotopes
The main isotopes of argon found on Earth are 40Ar (99.6%), 36Ar (0.34%), and 38Ar (0.06%). The most abundant isotope of argon is 40Ar. But other planets have different isotopes of argon.

## Production
Argon is gotten industrially by the fractional distillation of liquid air. About 700,000 tonnes of argon are produced worldwide every year. Argon is sometimes used for extinguishing (ending) fires.

Liquid argon is used in neutrino experiments and looking for dark matter. Argon is used to preserve food. Argon is sometimes used as the propellant in aerosol cans. Argon is also used as a preservative for such products as varnish, polyurethane, and paint. Argon has been used by athletes as a doping agent and has been banned as use. It is used to know how old rocks are.

## Related pages
* List of common elements
* Periodic table

## Sources
Capital

**Capital** can mean:

* Capital city (also called capital city or political capital), a city or town that contains the government of a country, state, or other area
* Capital (economics), how much real money a company or person has that they can use
* Capital (architecture), the top part of a pillar or column
* Capitalization, another word for "upper case" or majuscule
* Capital punishment, being put to death for doing a crime

## Related pages
* Capitol (disambiguation)
Mercure

**Mercure** may refer to:

* MERCURE, an atmospheric dispersion modeling CFD code developed by Électricité de France
* Mercure Hotels, a chain of hotels run by Accor
* French ship *Mercure* (1783)
* Dassault Mercure, a French airliner built in the 1970s
Radio telescope

: a radio telescope]]
A **radio telescope** is a type of antenna used for radio astronomy.  The majority look like a huge satellite television dish.  Stars shine, and the light can be seen with an ordinary telescope, but they also give off radio waves.  Scientists with radio telescopes receive these radio waves and use computers to learn about the stars.  Other things like black holes also give off radio waves, and radio telescopes are useful for learning about them too.

The dish is sometimes constructed of a conductive wire mesh whose openings are smaller than a wavelength. The information received by several radio telescopes in different places can be combined. This gives similar results to having a single dish as big as the distance between the telescopes. It can receive very faint signals, and see more details. The biggest telescope is a virtual radio telescope almost as big as the Earth, called the Event Horizon Telescope.

The radio telescope at the Parkes Observatory, Parkes, New South Wales was used by NASA to receive messages from the Apollo 11 moon landings.

## Related pages 
* Atacama Large Millimeter Array
Light year

A **light year** (symbol: **ly**)  is the distance that light travels in empty space in one year. Since the speed of light is about 300,000 km per second (about 186,000 miles per second), then a light year is 9.46 trillion kilometers (about 5.87 trillion miles), for AU, one light year is 63,241 AU. A light year is not a length of time.

The light year is used in astronomy because the universe is huge. Space objects such as stars and galaxies may be hundreds, thousands or millions of light years away.

## Example
Think of a star at a distance of 100 light years from us on Earth. Light leaves the star and takes 100 years to get to us. When we see the star's light, we are seeing that star as it was 100 years ago.

## Similar distance measurements
**Light minute* - The distance that light travels in one minute (about 18,000,000 km per minute, or 11,160,000 miles per minute).
:For example, our Sun is about 8 light minutes from Earth
**Light second* - The distance that light travels in one second (about 300,000 km per second, or 186,000 miles per second)
:For example, our Moon is about 1&frac14; light seconds from Earth

## References
LOL

]]

**LOL,** or **lol**, is an internet slang term that means "laugh(ing) out loud". It is commonly mistaken for "lots of love." LOL is often used in  meaning "That is really funny."  

It also means mute in Persian and is a native Dutch word (not an acronym) which means "fun" ("" means "funny"). In Welsh, lol means nonsense - e.g., if a person wanted to say "utter nonsense" in Welsh, they would say "rwtsh lol". LOL is usually used on the internet or when text messaging.

## Words similar to "LOL"
* **lolz**,** lulz**,** lul, lawls**: Sometimes used instead of **LOL**, but can have other meanings.
* **LOOOOOL**: For more . Any amount of "OL"s can be added to the end of LOL.  
* **LMAO**: Stands for "Laugh my ass off". Another way to say it is **LMFAO** ("Laugh my fucking ass off").
* **ROFL**: For " on the floor laughing". It is often combined with LMAO to make **ROFLMAO** ("Rolling on the floor laughing my ass off"). Another way to write this is **ROTFL**.
***ROTFLOL**: Rolling on the floor laughing out loud; used by Weird Al in the song "White and Nerdy".
***LEL:** Means the same thing as LOL, but with an E.
***kek:** The Japanese version of saying lol.

## Related page
* Lolcat

## References
Fluid ounce

A **fluid ounce** is a unit of volume in both the imperial system of units and the U.S. customary units system. However, the two measures are not quite the same:
* The Imperial fluid ounce is (1/160) of an imperial gallon or 8 fluid drams, about 1.734 cubic inches or exactly 28.413 07425 ml (as specified legally in *The Units of Measurement Regulations 1995*). This volume of water weighs very nearly 1 avoirdupois ounce.
* The U.S. fluid ounce is (1/128) of a U.S. fluid gallon, about 1.805 cubic inches or exactly 29.573 529 562 5 ml. This volume of water weighs about 1.04 avoirdupois ounces.
* U.S. law 21CFR101.9(b)(5)(viii) also defines a fluid ounce of exactly 30 ml, for use in nutrition labeling.

## Other websites 
*Volume Conversion Calculator
Meteor shower

]]

A **meteor shower** is an event when many meteors seem to come from one point in the night sky. These meteors are caused by meteoroids entering Earth's atmosphere at extremely high speeds on parallel paths. Most meteors are smaller than a grain of sand, so almost all of them burn up and never hit the Earth's surface.

A meteor shower is the result of an interaction between a planet, such as Earth, and streams of debris from a comet. Comets are dirty snowballs, made up of rock embedded in ice, orbiting the Sun. Each time a comet swings by the Sun in its orbit, some of its ice vaporizes and meteoroids will be shed. The meteoroids spread out along the entire orbit of the comet to form a meteoroid stream, also known as a "dust trail".

Most of our short-period meteor showers are the product of rare disintegrations, when large chunks break off a mostly dormant comet. Examples are the Quadrantids and Geminids. They originated from a breakup of asteroid-like objects, 2003 EH1 and 3200 Phaethon, respectively, about 500 and 1000 years ago. The fragments tend to fall apart quickly into dust, sand, and pebbles, and spread out along the orbit of the comet to form a dense meteoroid stream, which later moves into Earth's path.

The most visible meteor shower in most years are the Perseids, which peak on 12 August each year at over one meteor per minute. NASA has a useful tool to calculate how many meteors per hour are visible from your observing location.

The Leonid meteor shower peaks around 17 November of each year. About every 33 years, the Leonid shower produces a big meteor storm, peaking at thousands of meteors per hour. Leonid storms gave birth to the term "meteor shower" when it was first realised, during the November 1833 storm, that the meteors radiated from near the star Gamma Leonis. The last Leonid storms were in 1999, 2001 (two), and 2002 (two). Before that, there were storms in 1767, 1799, 1833, 1866, 1867, and 1966. When the Leonid shower is not *storming* it is less active than the Perseids.

## Related pages
* Meteor
*Meteor burst communication
*Panspermia

## References
Shape of the universe

s. The Virgo Supercluster – home of Milky Way – is marked at the center, but is too small to be seen in the image.]]

The **shape of the Universe** cannot be discussed with everyday terms, because all the terms need to be those of Einsteinian relativity. The geometry of the universe is therefore not the ordinary Euclidean geometry of our everyday lives.

According to the special theory of relativity, it is impossible to say whether two distinct events occur at the same time if those events are separated in space.  To speak of "the shape of the universe (at a point in time)" is naive from the point of view of special relativity. Due to the relativity of  we cannot speak of different points in space as being "at the same point in time" nor, therefore, of "the shape of the universe at a point in time".

What astrophysicists do is ask whether a particular model of the universe is consistent with what is known through observations and measurements of the universe. If the observable universe is smaller than the entire universe (in some models it is many orders of magnitude smaller or even infinitesimal), observation is limited to a part of the whole. 

Consideration of the shape of the universe can be split into two:
# *local* geometry, which relates especially to the curvature of the universe, especially in the observable universe, and
# *global* geometry, which relates to the topology of the universe as a whole, measurement of which may not be possible.

The observable universe is the basis for testing any model of the universe. It is a spherical volume (a ball) centered on the observer, regardless of the shape of the universe as a whole. Every location in the universe has its own observable universe, which may or may not overlap with the one centered on Earth.

Recent measurements have led NASA to state, "We now know that the universe is flat with only a 0.4% margin of error".  Within one model, the FLRW model, the present most popular shape of the Universe found to fit observational data is the infinite flat model. There are other models that also fit the data.

## References