cahya/simple-wikipedia huggingface dataset:
Volcanism (or vulcan activity) is the eruption of magma onto the surface of the Earth. 

Magma under the crust is under very great pressure. When folding and faulting occur, cracks or fractures appear. These are lines of weakness. 

When these lines of weakness develop downward in the crust and reach the magma, they will release the pressure in the magma. This allows magma to rise up along the lines of weakness and intrude into the crust. Some magma may even reach the Earth's surface as lava.

Volcanoes    

Volcanoes are the places where magma reaches the earth's surface. The type of volcano depends on the location of the eruption and the consistency of the magma.

Intrusions 

Intrusive volcanism is when magma is forced into the rocks that make up the Earth's crust.   When it cools and become solid while still underground, different features called plutons are formed. The rock formed is intrusive igneous rock.

These plutons will be exposed at the surface of land when the overlying rocks are removed after a long time of denudation (laid bare by erosion).

Major features formed by intrusive volcanicity include: batholith, laccolith, dyke, pipe and sill.
 Batholiths: Have large scale magma that has been solidified at the base of the mountain.
 Dyke: Is a small scale magma cooled within the earths crust that stands vertically to the existing rocks.
 Sill: Is a small scale magma cooled near the earths surface that lies horizontally to the existing rocks.
 Laccolith: A small scale magma that pushes the overlying layers of rocks to form a dome shaped structure.

Extrusions 
The molten magma under great pressure forces its way through the fissure of underground rocks and reaches the Earth's surface to form "igneous extrusion". 
Major extruded materials include gas, liquid and solid.

 Gas - sulphur, hydrogen, carbon dioxide and hot steam (geysers). When uprising magma decreases in pressure suddenly, gases within magma explode to the Earth's surface and cause destruction.
 Solid - pyroclast. Mainly composed of: country rock, fragments of solidified lava and fine materials (volcanic ash and dust). It can be classified by size into volcanic bombs, volcanic blocks, lapilli, volcanic ash and volcanic dust. 
 Liquid - lava, hot springs.

Features formed are:
 Caldera: a large depression in a former volcanic site. When it is filled with water it is called a 'caldera lake'. 
 Composite cones: a large volcanic mountain formed by solidified lava on the surface.
 Geysers: eruption of hot water and steam shooting into the air at regular intervals.
 Hot springs: springs of hot water that flow out continuously without shooting up into the air.

Notes

Other websites 

 

Volcanology
The Pacific Ocean is the body of water between Asia and Australia in the west, the Americas in the east, the Southern Ocean to the south, and the Arctic Ocean to the north. It is the largest named ocean and it covers one-third of the surface of the entire world. It joins the Atlantic Ocean at a line drawn  south from Cape Horn, Chile/Argentina to Antarctica, and joins the Indian Ocean at a line drawn  south from Tasmania, Australia to Antarctica.

As the Atlantic slowly gets wider, the Pacific is slowly shrinking. It does this by folding the sea floor in towards the centre of the Earth - this is called subduction.  This bumping and grinding is hard so there are many earthquakes and volcanoes when the pressure builds up and is quickly released as large explosions of hot rocks and dust. When an earthquake happens under the sea, the quick jerk causes a tsunami. This is why tsunamis are more common around the edge of the Pacific than anywhere else. Many of the Earth's volcanoes are either islands in the Pacific, or are on continents within a few hundred kilometers of the ocean's edge. Plate tectonics are another reason which makes Pacific Ocean smaller.

Other websites 

 EPIC Pacific Ocean Data Collection Viewable on-line collection of observational data
 NOAA In-situ Ocean Data Viewer  plot and download ocean observations
 NOAA PMEL Argo profiling floats Realtime Pacific Ocean data
 NOAA TAO El Niño data Realtime Pacific Ocean El Niño buoy data
 NOAA Ocean Surface Current Analyses – Realtime (OSCAR) Near-realtime Pacific Ocean Surface Currents derived from satellite altimeter and scatterometer data
The Indian Ocean is the ocean surrounded by Asia to the north, Australia and the Pacific Ocean to the east, the Southern Ocean to the south, and Africa and the Atlantic Ocean to the west. It is named for the river Indus and Ancient India on its north shore. The Bay of Bengal, the Arabian Sea, the Persian Gulf and the Red Sea are all parts of this ocean.

The deepest point in the Indian Ocean is in the Java Trench near the Sunda Islands in the east, 7500 m (25,344 feet) deep. The average depth is 3,890 m (12,762 ft). The Indian Ocean is the third largest ocean, 28,350,000 square miles in size. The majority is in the southern hemisphere.

Other websites 

 Maps of the indian Ocean
 Océan Indien in easy French
 NOAA In-situ Ocean Data Viewer  Plot and download ocean observations
 The Indian Ocean in World History: Educational Website Interactive resource from the Sultan Qaboos Cultural Center
 The Regional Tuna Tagging Project-Indian Ocean with details of the importance of Tuna in the Indian Ocean.. 
 Detailed maps of the Indian Ocean
 The Indian Ocean Trade: A Classroom Simulation 
 CIA - The World Factbook, Oceans: Indian Ocean
A basket is a container. It is usually light.

Basket makers use a wide variety of materials to create a basket, such as bark, willow rods, leaves, wire, plastic, paper, and rope.  There are three basic kinds of baskets—coiled, twined, or woven.  A woven basket is made of spokes and weavers:  the spokes run up and down and the weavers go over and under the spokes. A coiled basket is made by sewing rings of a fibrous material to the previous ring. Twined baskets have flexible weavers that are twined around the spokes in a variety of patterns. 

Basketmaking is so old that it features in myths from various cultures.  Baskets are used to carry babies, plants, fruit, cotton, and Easter eggs.  Coroners once used a basket coffin to collect bodies, thus the expression "a basket case" which meant the person was dead. 

In basketball, the basket is an open net fixed to a metal ring in which players try to throw the ball.

Basic English 850 words
Computer software, also called software, is a set of instructions and documentation that tells a computer what to do or how to perform a task. Software includes all different programs on a computer, such as applications and the operating system. Applications are programs that are designed to perform a specific operation, such as a game or a word processor. The operating system (e.g. Mac OS, Microsoft Windows, Android and various Linux distributions) is a type of software that is used as a platform for running the applications, and controls all user interface tools including display and the keyboard.

The word software was first used in the late 1960s to emphasize on its difference from computer hardware, which can be physically observed by the user. Software is a set of instructions that the computer follows. Before compact discs (CDs) or development of the Internet age, software was used on various computer data storage media tools like paper punch cards, magnetic discs or magnetic tapes.

The word firmware is sometimes used to describe a style of software that is made specifically for a particular type of computer or an electronic device and is usually stored on a Flash memory or ROM chip in the computer. Firmware usually refers to a piece of software that directly controls a piece of hardware. The firmware for a CD drive or the firmware for a modem are examples of firmware implementation.

Today, software has become an important part of our lives. software is used everywhere. software engineers are responsible for producing fault-free software which has literally become an essential part of our daily lives. Changeability and conformity are two of the main properties of software design. There are also different processing models for designing software including Build and Fix, Waterfall and Agile software processing design methods.

Types of Software 
The  different types of software can be put into categories based on common function, type, or field of use. There are three broad classifications:
 Application software are the computer programs for performing user tasks such as word processing and web browsers.
 System software is used to start and run computer systems and networks. This includes operating systems.
 Computer programming tools (also known as development software) are used to create application and system software. This is done by translating and combining computer program source code and libraries into executable RAMs. These include compiler and linker.

Related pages

 Computer program
 Free software
 software engineering

 
Computer science
A bed is a piece of furniture that people sleep on. It normally has a soft mattress on a bed frame. Many beds also have bed sheets to cover the mattress and additional sheets for the people to sleep under. People also use a pillow under their heads.  A bed comes in many different sizes including a single, double and king size.

History

In August 2020 archaeologists reported the discovery of the oldest grass bedding from Middle Paleolithic (at least 200,000 years ago). This was much older than the oldest previously known bedding. 

They found insect-repellent plants and ash layers beneath the bedding. This would have made a dirt-free, insulated base which helped to keep away insects. So early beds were little more than piles of straw or some other natural material (e.g. a heap of palm leaves, animal skins, or dried ferns).

Here's an example of what they said: "Several cultures have used ash as an insect repellent because insects cannot easily move through fine powder. Ash blocks insects' breathing and biting apparatus, and eventually dehydrates them. Tarchonanthus (camphor bush) remains were on top of the grass from the oldest bedding in the cave. This plant is still used to deter insects in rural parts of East Africa".

Mattresses stuffed with feathers were first used in Ancient Rome.

In Ancient Egypt, beds were considered to be status symbols. While the lower classes simply slept on a heap of palm bows or straw, the wealthy constructed wood platform beds that were ascended by stairs, were often curtained, and piled high with cushions for comfort.

In Ancient Rome, the bed was utilized as a multi-purpose reclining surface rather than just a place to sleep. Several beds, or "dining couches" were arranged around the perimeter of the home's living space, and friends and family would recline in bed while socializing, studying, and dining.

Types of beds 
There are several kinds of bed in use today. Several terms refer to the size of the mattress. Some kinds are usually temporary, such as camp cots, air mattresses, and hammocks.
 Single bed
 Double bed
 Bunk beds
 Twin beds
 Camp bed/ Cot
 Futon
 Cot/ Crib
 Carrycot/Portacrib
 Cradle
Hospital bed

References 

Basic English 850 words
Furniture
Asia is a large region on Earth mainly in the northern hemisphere. Asia is connected to Europe in the west, forming a continent called Eurasia, though sometimes it is viewed as a separate continent from Europe. Some of the oldest human civilizations began in Asia, such as Sumer, China, and India. Asia was also home to some large empires such as the Persian Empire, the Mughal Empire, the Mongol Empire, and the Ming Empire. It is home to at least 44 countries. Turkey, Russia, Georgia, Kazakhstan and Cyprus are partly are also considered european.

Area 

Asia includes a large amount of land. Covering about 30% of the world's land area, it has more people than any other continent, with about 60% of the world's total population. Stretching from the icy Arctic in the north to the hot and steamy equatorial lands in the south, Asia contains huge, empty deserts, as well as some of the world's highest mountains and longest rivers. 

Asia is surrounded by the Mediterranean Sea, the Black Sea, the Arctic Ocean, the Pacific Ocean, and the Indian Ocean. It is separated from Europe by the Pontic Mountains and the Turkish Straits. A long, mainly land border in the west separates Europe and Asia. This line runs North-South down the Ural Mountains in Russia, along the Ural River to the Caspian Sea, and through the Caucasus Mountains to the Black Sea.

Regions 

 East Asia
 Southeast Asia
 South Asia
 Central Asia
 West Asia
 North Asia

List of countries 

 Geologically in Europe and Asia
 Geologically in Europe and Asia

 Geologically in Europe and Asia

 Only Sinai Peninsula
 Geologically in Europe and Asia

 Geologically in Europe and Asia

 Geologically in Europe and Asia

 Geologically in Europe and Asia

Some countries are variously located in both Europe and Asia, namely Russia, Armenia, Azerbaijan, Georgia, Kazakhstan, Cyprus, and Turkey.

The Sinai Peninsula of Egypt lies in the Arabian peninsula, with the rest of the country lying in North-East Africa.

Related pages

 Asia Minor
 Asian Games
 Southeast Asia

References
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.

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 

Basic English 850 words
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 savings time - that way the time stays consistent the entire year.

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

References 

Time zones

fi:Aikajärjestelmä#UTC
Telegram television (also known as a TV) is a machine with a screen. Televisions receive broadcasting signals and change them into pictures and sound. The word "television" comes from the words tele (Greek for 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 cm tall, it would be 53 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.
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. 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 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 dawn or dusk the sky may appear red, orange, or even green and purple depending on how low the sun is and how close it is to night.

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 red.

Many things can be seen in the sky. There are objects from space like the Sun, Moon, and stars. There are also many weather events seen in the sky. For example, these can be clouds, rain, lightning, or fog. 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.

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

References 

Basic English 850 words
A tone language, or tonal language, is a language in which words can differ in tones (like pitches in music) in addition to consonants and vowels.

Chinese, Vietnamese, Thai, Punjabi, Yorùbá, Igbo, Luganda, Ewe, and Cherokee are tonal. The other languages, including Indo-European languages such as  English and Hindi, are not tone languages.

In some languages, it is pitch accent that is important instead. A word's meaning can then change if a different syllable is stressed. Examples include Ancient Greek, Hebrew, Swedish, Norwegian, Serbo-Croatian, Lithuanian, and some Asian languages like Japanese and Korean. However, pitch accent is different from tones.

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 "mā má mǎ mà ()" has four different words each pronounced in exactly the same way but with four different tones. If numbers identify the tones, they can be written ma1 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 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, 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 its use is to help Westerners. On the other hand, Vietnamese has a national script that always follows and uses the same style.

References
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 yenand Chinese Renminbi.

List of dollars
Australian dollar
Bahamian dollar
Barbadian dollar
Belize dollar
Canadian dollar
East Caribbean dollar
Hong Kong dollar
 Namibian dollar
New Zealand dollar
Singapore dollar
United States dollar
Zimbabwean dollar

Currency
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 together 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 

 
 (EU)
 

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 (EU)

 (EU)
 (EU) Geologically in Europe and Asia
 (EU)
 (EU) Geologically in Europe and North America

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 (EU)
 (EU)
 Geologically in Europe and Asia
 (EU)
 (EU)
 (EU)
 Geologically in Europe and North America

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 Geologically in Europe and Asia

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 Geologically in Europe and Asia

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

Laurasia
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

Arctic
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 is -s (e.g., cat is singular, and cats 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 ending.

References 

Grammar
Oceania is a name used in geography for the region made up of Australia, Polynesia, Melanesia, and several other island nations in the surrounding area. It is often listed as one of 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 and the Americas, including Australasia, 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, 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 seperately 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, 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.

References

 

Oceania
The Southern Ocean is the ocean around Antarctica. It means the waters of the Atlantic, Pacific, and Indian Oceans around the continent of Antarctica. Since the 1770s geographers have discussed its limits. Nowadays, sixty degrees south latitude is often accepted. Some people call this ocean the Antarctic Ocean.

The total area is 20,327,000 km², and the coastline length is 17,968 km.

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 

 
Geography of Antarctica
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

Languages of Europe
Romance languages
Catalonia
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. It can be described as both a science and a technique: a science because it has its own theories and 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, or 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 in psychology as well. The term derives from the Greek: σημειωτικός, romanized: sēmeiōtikos, "observant of signs" (from σημεῖον sēmeion, "a sign, a mark"). For the Greeks, "signs" occurred in the world of nature, and "symbols" in the world of culture. As such, Plato and Aristotle explored the relationship between signs and the world.

The general study of signs that began in Latin with Augustine culminated with the 1632 Tractatus de Signis of John Poinsot, and then 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.  

Semiotics is usually divided into three parts:
Semantics -  what was the meaning of the words or signs used; 
Pragmatics - who said it, to whom and in what circumstances and 
Syntactics - the formal rules of the language used.

The major branches of semiotics include:
Biosemiotics
Zoosemiotics
Semiotics of culture

Other page 
Philosophy of language

References

Language
Colour or color is a property of light as seen by people. In Commonwealth English, it is spelled “colour” (notice the U), while in American English it is “color” (no U).

The most common colour names are: 
 Red
 Orange
 Yellow
 Green
 Cyan
 Blue
 Magenta
 Purple
 White
 Black
 Gray (American English)
 Grey (Commonwealth English)
 Silver
 Pink
 Maroon
 Brown
 Beige
 Tan
 Peach
 Lime
 Olive
 Turquoise
 Teal
 Navy blue
 Indigo
 Violet

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

People who can not see colours or have a distorted sense of colour are called colour blind. Most colour blind people are male.

Colours are sometimes added to food. Food colouring is used to colour food, but some foods have natural colourings, like beta carotene.

When something has no colour, it is 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 colourless material because it can still have a colour, like stained glass.

Related pages

 List of colours

References 

Basic English 850 words
Color
Vision
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 prevents 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 mg 
 Children and adults: 45–60 mg 
 Pregnant women: 70 mg 
 Mothers breast feeding: 90–95 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 

Diseases
Vitamin deficiencies
An ion is an electrically charged atom or group of atoms.
It can be made from an atom, or from a group of atoms (molecule). It is "charged" so it will move near electricity. This is because atoms are made of three smaller parts:

 neutrons (with no charge),
 number of protons with positive charges and
 equal number of negatively-charged electrons. 

An ion has unequal numbers of protons and electrons. Making an ion from an atom or molecule is called ionization.

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) 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

Related pages
List of ions

References 

Chemistry
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 

Science
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
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 gotten from the Greek word ἀργός meaning "lazy" or "inactive" because it doesn't react a lot.

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 is a heavier gas than helium, so if a balloon is filled with argon, it would sink.

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.

40Ar is made by the decay of 40K with a half-life of 1.25 billion years by electron capture or positron emission. Because of this, it is used in knowing how old rocks are.

Uses 
Argon is often used when welding steel and similar work, to push away the air around the weld, so the oxygen in the air can't join with the metal being welded. It can also be used in neon lights for a purple color. Argon is used in the poultry industry to asphyxiate birds. Argon is sometimes used for putting off 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

Noble gases
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

Telescopes