title: Butter

paragraphs: Butter is a dairy food. It is made by moving the cream from whole milk for a long time. The fat in the milk separates from the liquid. The fat is butter.

paragraphs: Butter is often put on on bread, as a main ingredient in biscuits, as a shortening agent in some baking and cooking recipes, and for frying foods.

paragraphs: Often, butter is made from cows' milk, butter can also be made from the milk of other mammals, like sheep, goats, buffalo, and yaks. Salt, flavorings and preservatives are sometimes added to butter.

paragraphs: Many people use butter in their foods instead of oil.

paragraphs: Cultured butter is a butter made from a fermented cream. Sweet cream butter is butter made from pasteurized fresh cream. Raw cream butter is butter made from fresh or cultured unpasteurized cream.


title: Cold War

paragraphs: The Cold War was the tense relationship between the United States (and its allies), and the Soviet Union (the USSR and its allies) between the end of World War II and the fall of the Soviet Union. It is called the "Cold" War because the US and the USSR never actually fought each other directly. Instead, they opposed each other in conflicts known as proxy wars, where each country chose a side to support.

paragraphs: Most of the countries on one side were allied in NATO whose most powerful country was the United States. Most of the countries on the other side were allied in the Warsaw Pact whose most powerful country was the Soviet Union.

paragraphs: The Western Bloc was the name of the capitalist countries led by the United States. The North Atlantic Treaty Organization (NATO) is an alliance created in 1949 which included the US, United Kingdom, France, West Germany, Canada, Netherlands, Belgium, Luxembourg, Spain, Portugal, Italy, Norway, Iceland, Denmark, Greece, and Turkey. Other countries allied with the Western Bloc include Israel, Japan, South Korea, Thailand, Iran (1945-1979), Pakistan, Malaysia, Philippines, South Africa, Australia and New Zealand.

paragraphs: The Eastern Bloc was the group of socialist countries led by the Soviet Union (USSR). The Warsaw Pact was an alliance created in 1955 which included the USSR, Albania (until 1968), Bulgaria, Czechoslovakia, East Germany, Hungary, Poland, and Romania. Other countries allied with the Eastern Bloc included Angola (1975-1991), Ethiopia (1974-1991), Cuba (1959-1991), Mongolia, North Korea, China (1949-1966) and Vietnam (1975-1991).

paragraphs: In February 1917, Tsar (King) Nicholas II of the Russian Empire was overthrown because people were unhappy with their living conditions, especially during World War I. The new government in Russia was a democratic socialist government. Unfortunately, it was ineffective, and people were still unhappy. In November 1917, a communist group called the Bolsheviks led by Vladimir Lenin overthrew the new government. They were supported by groups of workers called Soviets. The Bolsheviks created a new communist government called the Russian Soviet Federative Socialist Republic (called simply Soviet Russia or the Russian SFSR).

paragraphs: However, not everyone supported the communists. Many countries that had been a part of the Russian Empire had left, such as Latvia, Lithuania, Estonia, Poland, and Finland. The Russian Civil War began, with the Russian SFSR's "Red Army" fighting against the "White Army", the group of all Russians against the communists. The White Army was not very united or organized. The Allied Powers of World War I, such as the United States, United Kingdom, and France, invaded Russia to support the White Army. Soviet Russia eventually won the war in 1922, and established the Union of Soviet Socialist Republics (Soviet Union), along with the newly formed Socialist Republics of Ukraine, Belarus, Armenia, Azerbaijan and Georgia.

paragraphs: The start of the Cold War in 1947 was due to a belief that all governments would become either communist or capitalist. The Western allies feared that the Soviet Union would use force to expand its influence in Europe, and was especially concerned that Soviet agents had obtained information on making the Atom Bomb after the war.

paragraphs: Both groups of nations had opposed Nazi Germany. The Soviet Union had sporadically co-operated with Germany and shared in the division of Poland in 1939, but Germany turned against the Soviet Union in June 1941 with Operation Barbarossa.

paragraphs: After Second World War, Germany was left in ruins. The victorious Allies that occupied it split it into four parts. In the western half of Germany, one part was given to the United States, one to the United Kingdom, and one to France. The Eastern half was occupied by the USSR. The city of Berlin was also split among the four countries, even though it was entirely within the Eastern half.

paragraphs: The Federal Republic of Germany ("Bundesrepublik Deutschland" or BRD), or West Germany, was recognized by the Western allies in June 1949. It was a capitalist democracy. West Berlin was considered a part of the country. The USSR named their section of Germany the German Democratic Republic ("Deutsche Demokratische Republik" or DDR), or East Germany, later in 1949. It was a communist dictatorship.

paragraphs: From April 1948 to May 1949, the Soviets blockaded West Berlin to prevent the city from using West Germany's currency. The United States and its allies supplied the city through airplanes until September 1949 in what became known as the Berlin Airlift. Many East Germans wanted to live in West Germany due to its greater quality of life and political freedoms. Thus, in 1961, the East German government built the Berlin Wall, dividing the two halves of the city. It was heavily guarded to prevent people from escaping to the West. It was considered a symbol of the Cold War and the Iron Curtain that divided Europe.

paragraphs: Espionage, "spying" has been around for a long time, and was very important during the Cold War. After its successful nuclear espionage in the Manhattan Project the USSR built up its spy organs, especially the KGB. The Central Intelligence Agency led US efforts abroad, while the FBI did counterespionage. Catching foreign spies was among KGB functions, as well as fighting domestic subversion.

paragraphs: In the USSR, the dictator Joseph Stalin died and Nikolai Bulganin and Nikita Khrushchev (1953) took his place. Khrushchev later took sole control of the USSR. Khrushchev's Secret Speech marked a period of de-Stalinization and Khrushchev tried to undo many of the things Stalin did (such as the Gulag prison camps and 'cult of personality').

paragraphs: In the United States, there was a "Red Scare", and when the USSR detonated its own atom bomb, there was a great deal of political fallout. Famous people, in many fields who had been Communist sympathizers in the past lost their positions. Many actors were 'blacklisted' and were not hired to act in movies, ruining their careers. Senator Joseph McCarthy accused some important Americans of being communists, including some high government officials.

paragraphs: The 1950s were the beginning of the space race between the United States and USSR. It began with the USSR putting the Sputnik 1 satellite into orbit around the Earth, making the Soviet Union the first country in space. The United States responded by starting NASA, and soon sent up its own satellites. The Soviet Union also sent the first man (Yuri Gagarin) into Earth orbit, claiming that this proved communism was the better ideology.

paragraphs: In the 1950s, the United States (under president Dwight Eisenhower) created a policy called "New Look," cutting defense spending and increasing the number of nuclear weapons as a deterrent in order to prevent the Soviet Union from attacking the USA. The USSR also increased their nuclear force, resulting in mutual assured destruction.

paragraphs: In the Suez Crisis of 1956, the Cold War alliances were broken for the first time with the Soviet Union and United States favouring one side, and Britain and France the other. Later that year, the Western allies did not interfere when Soviet troops suppressed an anti-communist revolution in Hungary.

paragraphs: United States Vice-President Richard Nixon engaged in several talks with Nikita Khrushchev during the 1950s. One of these was the 1959 "Kitchen Debate" in a model kitchen in Moscow. These debates highlighted the political and economic differences between the USA and the USSR. The following year, the United States U-2 spy plane crashed in the Soviet Union. Tensions between the two countries increased.

paragraphs: After the United States tried to invade Cuba and failed (Bay of Pigs), the Soviet Union attempted to supply Cuba with nuclear missiles. These missiles in Cuba would have allowed the Soviet Union to effectively target almost the entire United States. In response the United States sent a large number of ships to blockade Cuba thus preventing the Soviet Union from delivering these weapons. The United States and Soviet Union came to agreement that the Soviet Union would no longer give nuclear weapons to Cuba as long as the United States does not invade Cuba again. This was the highest period of tension during the Cold War and it was the closest the world came to a nuclear war, with possible global conflict to follow.

paragraphs: After the agreement that ended the Cuban Missile Crisis, relations between the two sides eased up. Several treaties, designed to reduce the number of nuclear weapons, were signed. During this period of Détente, the United States began building a good relationship with China, a previous ally of Russia.

paragraphs: The policy of détente ended in 1981, when the U.S. president Ronald Reagan ordered a massive military massing to challenge the Soviet Union's influence around the world. The United States began to support anti-communists all over the world with money and weapons. The idea was to help them overthrow their communist governments.

paragraphs: The Soviet Union had a slow economy during this decade because military spending was at an all-time high. They tried to keep up with the United States in military spending, but could not. In the Soviet war in Afghanistan starting in 1979, the Soviet Union had a difficult time fighting resistance groups, some of them armed and trained by the United States. The Soviet Union's failed invasion of Afghanistan is often compared to the United States' failure during the Vietnam War.

paragraphs: In the late 1980s the new Soviet President Mikhail Gorbachev made an effort to make an ally of the United States to fix world problems caused by the war, with the ultimate aim of eliminating nuclear weapons completely. However, this did not take place because the President of the United States, Ronald Reagan, insisted on having a nuclear missile defense system. The people of the Soviet Union were divided on their feelings about this. Some wanted President Gorbachev to fight harder to eliminate nuclear weapons, while others did not want him to be talking to the United States at all. These mixed feelings created an atmosphere of political in-fighting, and the people were no longer united behind one goal. Because of this, the Communist Party started to crumble.

paragraphs: After the fall of the Berlin Wall in 1989 and without Communist rule holding together the countries that comprised the Soviet Union, the USSR broke into smaller countries, like Russia, Ukraine, Lithuania and Georgia. The nations of Eastern Europe returned to capitalism, and the period of the Cold War was over. The Soviet Union ended in December 1991.

paragraphs: Not all historians agree on when the Cold War ended. Some think it ended when the Berlin Wall fell. Others think it ended when the Soviet Union collapsed in 1991.


title: Mainland China

paragraphs: Mainland China, also called the Chinese Mainland, is the part of China not including the Republic of China controlling Taiwan, Kinmen, Matsu, and the Pescadores. The term also excludes Hong Kong and Macau.

paragraphs: In the Qing Dynasty (Manchu Dynasty), all of Mainland China, Hong Kong, Macau, Taiwan, Kinmen, Matsu, the Pescadores, and Mongolia were part of the Manchu Empire. Taiwan, Hong Kong, and Macau were colonized by foreigners for some years (Taiwan to the Japanese, Hong Kong to the British, and Macau to the Portuguese).

paragraphs: By the end the Qing Empire, China became Nationalist China (the Republic of China) and it got Taiwan back in 1945. After the Communists (the People's Republic of China) took over most of China, the Nationalists kept only Taiwan, Kinmen, Matsu, and the Pescadores. Mongolia became an independent state later.

paragraphs: Since then, Communist China only includes the part on the continent (mainland) and some small islands that are very near (the largest communist island is Hainan). This region is Mainland China.

paragraphs: Later Hong Kong and Macau were returned to the government of China, but because the government calls them "special administrative regions" under a "one country, two systems" idea, they are still not thought of as part of Mainland China.


title: Capital city

paragraphs: A capital city (or capital town or just capital) is a city or town, specified by law or constitution, by the government of a country, or part of a country, such as a state, province or county. It usually serves as the location of the government's central meeting place and offices. Most of the country's leaders and officials work in the capital city.

paragraphs: Capitals are usually among the largest cities in their regions; often they are the biggest. For example, Montevideo is Uruguay's capital as well as its biggest city. The capital city may also be the most important center of commerce, as in London or Bangkok.

paragraphs: However, a capital is not always the largest city in a country. For example, the capital of the India is New Delhi, which is smaller than Mumbai; and the capital of Pakistan is Islamabad, which is smaller than Karachi. Also, in countries with subdivisions like the United States, the capital cities or towns of the federated states are often not the largest or most populated town. For example, New York City is the biggest city in the United States and in New York but is not the capital of either.

paragraphs: An unusual case exists in Canada; the federal capital, Ottawa, is not the largest city in its province, Ontario, which is Toronto. But Toronto happens to be the capital of the province of Ontario. This way, Toronto is both a capital and a non-capital, depending on how you see it, as a city in a country or part of it.

paragraphs: Some countries have more than one capital, often for different purposes, like Bolivia, which has two (Sucre and La Paz); and South Africa, which has three (Pretoria, Cape Town, and Bloemfontein). In a city-state such as Singapore or Monaco, or the Vatican City, the capital is the country.

paragraphs: Not all countries have capitals. Nauru is a country that does not officially have a capital, but the district of Yaren, which is where the government is, can be called the "de facto" capital. Also, although many people consider the city of Bern in Switzerland to be the capital of the country, it is in fact not the case by law, but has the status of "" by the government which is based there.

paragraphs: Capitals can be in cities that are already there like London or Rome, or a new town can be built and made the capital like Canberra and Alexandria. Countries can change capitals from time to time. Several cities have been the capital of China. The United States once had its capital in Philadelphia and later in New York City but moved to the new city of Washington, D.C. in 1800. Rio de Janeiro was the capital of Brazil, until the new city of Brasilia was built between 1956 and 1960.

paragraphs: Most countries have their seat of government within their capital city, though some do not. Malaysia has their capital at Kuala Lumpur but their seat of government is at Putrajaya. In the Netherlands, the constitution says that Amsterdam is the "de jure" capital, but the government is in The Hague.


title: Climate

paragraphs: Climate means the usual condition of the temperature, humidity, atmospheric pressure, wind, rainfall, and other meteorological elements in an area of the Earth's surface for a long time. In simple terms climate is the average condition for about thirty years. Climate and weather are different. Weather is the day to day conditions in the atmosphere. The types of climates are: Tropical, Desert/dry, Temperate, Polar, Mediterranean.

paragraphs: The latitude, ground, and height can change the climate of a location. It is also important to note if oceans or other large bodies of water are nearby. Climates are most commonly classified by temperature and precipitation. The most commonly used classification was the Köppen climate classification, first made by Wladimir Köppen. The Thornthwaite system, which was used from 1948, not only uses temperature and precipitation information, but evapotranspiration too. This makes it useful for studying how many different kinds of animal species there are, and about the things that could happen when climates change. The Bergeron and Spatial Synoptic Classification systems focus more on where the air masses which help make climates come from.

paragraphs: Climates can change after a long time. Nowadays people are making the world warmer.


title: Fold (geology)

paragraphs: Rock often deforms in such a way that it bends instead of breaking. This is called a fold. The term fold is used in geology when one or a stack of originally flat, level surfaces, such as sedimentary strata, are bent or curved as a result of pressure and high temperature. The basic cause is likely to be some aspect of plate tectonics.

paragraphs: When two forces act towards each other from opposite sides, rock layers are bent into "folds". The process by which folds are formed due to compression is known as folding. Folding is one of the endogenetic processes; it takes place within the Earth's crust.

paragraphs: Folds in rocks vary in size from microscopic crinkles to mountain-sized folds. They occur singly as isolated folds and in extensive fold trains of different sizes, on a variety of scales. A set of folds distributed on a regional scale constitutes a "fold belt", a common feature of orogenic zones.

paragraphs: There are large-scale and small-scale folds. Large-scale folds are found mainly along a collision boundary between two tectonic plates.

paragraphs: The upfold is called an anticline. The downfold is called a syncline.

paragraphs: The imaginary line joining the highest points along the upfold is called the crest line.

paragraphs: The flanks of a fold are known as the limbs.

paragraphs: The central line from which the rock strata dip away in opposing directions is called the axis of fold.

paragraphs: According to the degree of folding of the layers, folds can be classified into five main types.

paragraphs: Large depressions called geosynclines form between plates. Seas filled the geosynclines and rivers flowing into them carried sediments (sand and silt) which build up on the sea bed.

paragraphs: Over millions of years the sediments were compressed, by their own weight, into sedimentary rocks, e.g. sandstone, limestone etc.

paragraphs: Large-scale folding will develop parallel ranges of round-top mountains along destructive plate boundaries. These mountains are known as fold mountains.


title: Volcanism

paragraphs: Volcanism (or vulcan activity) is the eruption of magma onto the surface of the Earth.

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

paragraphs: 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.

paragraphs: Volcanoes are 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.

paragraphs: 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.

paragraphs: 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).

paragraphs: Major features formed by intrusive volcanicity include: batholith, laccolith, dyke, pipe and sill.

paragraphs: 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".

paragraphs: Major extruded materials include gas, liquid and solid.


title: Pacific Ocean

paragraphs: 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.

paragraphs: 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.


title: Antarctica

paragraphs: Antarctica is the Earth's southernmost continent. It is on the South Pole. It is almost entirely south of the Antarctic Circle. Around Antarctica is the Southern Ocean. It is the fifth-largest continent in area after Asia, Africa, North America, and South America. About 99% of Antarctica is covered by ice. This ice averages at least 1.6 kilometers (1.0 miles) thick.

paragraphs: Antarctica is the coldest, driest and windiest continent. It is also, on average, the highest of all the continents. Antarctica is considered a desert. It has yearly precipitation of only 200 mm (8 inches) near the sea and far less inland. No humans live in Antarctica permanently. However, about 1,000 to 5,000 people live through the year at the science stations in Antarctica. Only plants and animals that can live in cold live there. The animals include penguins, seals, nematodes, tardigrades and mites. Plant life includes some grass and shrubs, algae, lichen, fungi, and bacteria.

paragraphs: The first known sighting of the continent was in 1820. Antarctica was mostly forgotten for the rest of the 19th century. This was because of its hostile environment, few resources, and isolation. The first official use of the name "Antarctica" as a continental name in the 1890s is said to have been used by Scottish cartographer John George Bartholomew.

paragraphs: The Antarctic Treaty was signed in 1959 by 12 countries. More countries have signed the treaty since then. So far, 46 countries have signed the treaty. The treaty declares that military activities and mineral mining are against the law. However, it supports scientific research. It also helps the continent's ecozone. More than 4,000 scientists from different nations and different interests experiment together.

paragraphs: Antarctica is covered by an ice sheet about four kilometres thick. Under the ice it is mostly land, although the ice shelves are over the ocean. The Transantarctic Mountains divide the land between East Antarctica in the Eastern Hemisphere and West Antarctica in the Western Hemisphere.

paragraphs: Antarctica has some important features hidden by the ice. One is Lake Vostok, which has been covered by ice for at least 15 million years. The lake is 250 km long and 50 km wide. Another is the huge Gamburtsev mountain chain, which are the size of the Alps, yet entirely buried under the ice. The Gamburtsev range has a nearby massive rift valley similar to the East African Great Rift Valley. It is called the Lambert system. Scientists used radar that can work under ice to survey the whole of Antarctica.

paragraphs: Scientists say Antarctica used to be much further north and much warmer, moving to where it is now through continental drift. From 2011 to 2013, scientists collected fossils of frogs, water lilies, and shark and ray teeth, showing that these life forms used to live on Antarctica. The frog fossils were about 40 million years old. Scientists say marsupials, animals that keep their babies in pouches, could have started in South America, migrated to a warm ancient Antarctica, and gone to Australia from there.

paragraphs: Few land plants grow in Antarctica. This is because Antarctica does not have much moisture (water), sunlight, good soil, or a warm temperature. Plants usually only grow for a few weeks in the summer. However, moss, lichen and algae do grow. The most important organisms in Antarctica are the plankton which grow in the ocean.

paragraphs: One important source of food in the Antarctic is the krill, which is a general term for the small shrimp-like marine crustaceans. Krill are near the bottom of the food chain: they feed on phytoplankton and to a lesser extent zooplankton. Krill are a food form suitable for the larger animals for whom krill makes up the largest part of their diet. Whales, penguins, seals, and even some of the birds that live in Antarctica, all depend on krill.

paragraphs: Whales are the largest animals in the ocean, and in Antarctica. They are mammals, not fish. That means that they breathe air and do not lay eggs. Many different kinds of whales live in the oceans around Antarctica.

paragraphs: Whalers have hunted whales for hundreds of years, for meat and blubber. Nowadays most whaling is done in the Antarctic area.

paragraphs: Penguins only live south of the equator. Several different kinds live in and around Antarctica. The biggest ones can stand nearly 4 feet (1.2m) tall and can weigh almost 100 pounds (40 kg). The smallest kinds are only about one foot (30 cm) tall. Penguins are large birds that swim very well but cannot fly. They have black backs and wings with white fronts. Their feathers are very tightly packed and make a thick cover. They also have a layer of woolly down under the feathers. The feathers themselves are coated with a type of oil that makes them waterproof. A thick layer of blubber also keeps them warm. Penguins eat fish and are at home in the ocean. They come up on the land or ice to lay their eggs and raise the chicks. They nest together in a huge group.

paragraphs: The largest animal in Antarctica that lives entirely on land is a wingless midge.

paragraphs: For a long time, people had believed that there was a great continent in the far south of Earth. They thought this "Terra Australis" would "balance" the lands in the north like Europe, Asia and North Africa. People have believed this from the times of Ptolemy (1st century AD). He suggested this idea to keep the balance of all known lands in the world. Pictures of a large land in the south were common in maps. In the late 17th century, people discovered that South America and Australia were not part of the mythical "Antarctica". However, geographers still believed that Antarctica was much bigger than it really was.

paragraphs: European maps continued to show this unknown land until Captain James Cook's ships, HMS "Resolution" and "Adventure", crossed the Antarctic Circle on 17 January 1773, in December 1773. They crossed it again in January 1774. In fact, Cook did come within about of the Antarctic coast. However, he was forced to go back because of ice in January 1773.

paragraphs: The first confirmed sighting of Antarctica were by three different men. According to different organizations, ships captained by three men saw Antarctica in 1820. The three men were Fabian von Bellingshausen (a captain in the Russian Imperial Navy), Edward Bransfield (a captain in the Royal Navy), and Nathaniel Palmer (an American seal hunter out of Stonington, Connecticut). The first recorded landing on mainland Antarctica was by the American sealer John Davis. He landed on West Antarctica on 7 February 1821. However, some historians are not sure about this claim.

paragraphs: People began discovering different parts of Antarctica and mapping them. This was slow work because they could only work in the summer. At last a map was made, and people began to talk about exploring the land, not only the sea. However, this would have been very hard work. They would have to break through the ice that was around Antarctica. Then they would have to land on it and bring in enough things to live on while they explored the land.

paragraphs: The first serious exploration of the Antarctic land was the Nimrod Expedition led by Ernest Shackleton in 1907–09. They were the first to climb Mount Erebus and to reach the South Magnetic Pole. Shackleton himself and three other members of his expedition made several firsts in December 1908 – February 1909. They were the first humans to cross the Ross Ice Shelf, and the Transantarctic Mountain Range (via the Beardmore Glacier). They were the first to set foot on the South Polar Plateau.

paragraphs: Robert Falcon Scott, the most well known of all of the explorers, wanted to be the first man to reach the South Pole. At the same time, another team from Norway lead by Roald Amundsen started. They both raced each other to the South Pole, but in the end Amundsen won because he had made a good use of his sleigh dogs. Scott had used ponies and motor sleds, but when he got to the South Pole he found a message from Amundsen, showing that he had beaten Scott.

paragraphs: On his way back, Scott and three companions met a blizzard and froze to death while waiting for it to finish. The people who found him eight months later also found his records and diary, which he had written to the day he died.

paragraphs: Climate change and global warming are showing effects in Antarctica, particularly the Antarctic Peninsula.

paragraphs: No one lives in Antarctica all the time. People who go to Antarctica are there to learn about Antarctica, so most of the people who live there are scientists. Most live at national science stations on the coast. Some bases are far from the sea, for example at the South pole. They study the weather, animals, glaciers, and the Earth's atmosphere. Some scientists drill ice cores to find out about the weather long ago. People who work in the Antarctic must be careful, because a blizzard can start any time and anywhere. When they go far away from their shelter, they must always take lots of food just in case.

paragraphs: Today, people explore Antarctica using snowmobiles, which are faster than dogs and can pull heavier loads. Many come to Antarctica just for a short visit. There are companies in South America that have vacations to Antarctica, so people pay to go there on a ship. Some people take their own boats.


title: South Pole

paragraphs: The South Pole is the most southern point on the Earth. It is in Antarctica and is the center of the Southern Hemisphere. From the South pole, everywhere is North.

paragraphs: The geographic North and South poles are the poles the earth spins around, the ones people see on a globe where all the north/south lines meet. These poles stay in the same place, and are usually the ones we mean if we just say North or South Pole. People can tell that they are at these poles by looking at the stars (at the poles, a star just circles around at the same height, never dipping to the horizon). The Sun rises once a year and gives the South Pole half a year of summer but it is always cold. When the Sun sets half a year later it makes half a year of winter which is even colder. The South Pole is always cold because the Sun never rises high in the sky.

paragraphs: The south magnetic pole is something different. It is defined by the Earth's magnetic field, as roughly where a magnetic compass needle points. People can tell they are near these poles by looking at a compass.

paragraphs: The South Pole is hard to reach. Unlike the North pole, which is covered by the sea and flat sea-ice, the South Pole is on a mountainous continent. This continent is called Antarctica. It is covered by thick ice (more than a mile thick in the centre). The south Pole is very high up, and is very windy. It is far from places where people live, and ships going there often have to find their way through thick sea ice. Once ashore, land-travelling explorers have to travel more than a thousand miles to get to the pole. They must cross a floating ice shelf, then up onto the ice-covered land, up steep mountain glaciers covered in broken, twisted ice slowly sliding to the sea, and across a high level land ("plateau") covered in ice and swept by strong freezing winds.

paragraphs: Two expeditions early in the 20th century, led by Robert Falcon Scott and then Ernest Shackleton, failed to reach the South Pole, but returned safely. Shackleton turned back quite close to the pole, but it was late in the season and supplies were low. He knew that he would be risking the lives of his men, so he turned back.

paragraphs: The first men to reach the South Pole were a group from Norway led by Roald Amundsen. They arrived at the Pole on December 14, 1911 and left the Norwegian flag. Amundsen and his men returned home safely. Amundsen's story is one of excellent planning, good leadership, and willingness to learn from others: this made extreme endurance unnecessary, and perhaps made the successful expedition less of a story, and therefore perhaps less famous, than the next one.

paragraphs: The most famous South Pole expedition is perhaps the one that failed badly. This was the British expedition (not just UK, it included people from the British Empire, who at that time were considered British citizens) led by Robert Falcon Scott. Scott and four other men, dragging their equipment on sledges, had hoped to be first to the Pole. When they arrived, they saw a Norwegian flag. A letter left for Scott showed that Amundsen and his men had beaten them by a month, by using dogs to pull their sledges.

paragraphs: On their journey back from the Pole, Scott's team found that food "dumps" were short of supplies, particularly kerosene. Kerosene was very important: not just for cooking but for melting ice. Once it ran out, they would have no water to drink. One man collapsed and died while walking. Oates knew his frostbitten feet could not carry him back to base, and that he might delay his companions and risk their lives. He committed suicide by walking out of their tent into the cold. Scott and his remaining two companions died of starvation, thirst, and cold - trapped in the tent by bad weather until their supplies ran out. Next spring, the three bodies in the tent were found by a team from the main part of the expedition - who had spent the winter in the expeditions's hut by the sea. Scott's letters to his wife, written in the tent when he knew he was going to die, have just (Jan 2007) been made public.

paragraphs: Apart from Ernest Shackleton's expedition to cross the Antarctic (another heroic failure, but Shackleton saved all his men, after a very courageous sea crossing in an open boat, and a crossing of an unknown mountain range while starving and freezing), this was the end of the "heroic" age of exploration. Motors, Planes, Radios, and GPS ensured that following expeditions were never truly "unsupported".

paragraphs: Today there is an American science base at the South Pole. It is named the Amundsen-Scott South Pole Station to honor the two explorers.

paragraphs: The South Pole has a desert climate. It almost never gets any precipitation. Air humidity is near zero. However, high winds can cause the blowing of snowfall, and the accumulation of snow amounts to about per year. The former dome seen in pictures of the Amundsen-Scott station is partially buried due to snow storms, and the entrance to the dome had to be regularly bulldozed to uncover it. More recent buildings are raised on stilts so that the snow does not build up against the sides.


title: Indian Ocean

paragraphs: 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.

paragraphs: 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.


title: Arctic Ocean

paragraphs: The Arctic Ocean is the ocean around the North Pole. The most northern parts of Eurasia and North America are around the Arctic Ocean. Thick pack ice and snow cover almost all of this ocean in winter, and most of it in summer. An icebreaker or a nuclear-powered submarine can use the Northwest Passage through the Arctic Ocean to go between the Pacific and Atlantic oceans.

paragraphs: The ocean's area is about 14.056 million km, which is the smallest of the world's 5 oceans, and it has of coastline. The central surface covered by ice about thick. The biology there is quite special. Endangered species there include walruses, whales and polar bears. Year by year the Arctic Ocean is becoming less icy, as a result of global warming.

paragraphs: The average depth of the Arctic Ocean is . The deepest point is in the Eurasian Basin, at .

paragraphs: The Arctic Ocean covers an area of about 14,056,000 km. The coastline is 45,390 km (28,200 mi) long It is surrounded by Eurasia, North America, Greenland, and by several islands.

paragraphs: It is generally taken to include Baffin Bay, Barents Sea, Beaufort Sea, Chukchi Sea, East Siberian Sea, Greenland Sea, Hudson Bay, Hudson Strait, Kara Sea, Laptev Sea, White Sea and other bodies of water. It is connected to the Pacific Ocean by the Bering Strait and to the Atlantic Ocean through the Greenland Sea and Labrador Sea.

paragraphs: Countries bordering the Arctic Ocean are: Russia, Norway, Iceland, Greenland, Canada and the United States.

paragraphs: The Arctic Ocean is in a polar climate. Winters are characterized by the polar night, cold and stable weather conditions, and clear skies.

paragraphs: The temperature of the surface of the Arctic Ocean is fairly constant, near the freezing point of seawater. Arctic Ocean consists of saltwater but its salinity is less than other oceans. The temperature must reach −1.8 °C (28.8 °F) before freezing occurs.

paragraphs: Ice covers most of the Arctic Ocean. It covers almost the whole ocean in late winter and the majority of the ocean in late summer. Much of the Arctic ice pack is covered in snow for about 10 months of the year. The maximum snow cover is in March or April — about 20 to 50 cm (7.9 to 19.7 in).

paragraphs: The climate of the Arctic region has varied significantly in the past. As recently as 55 million years ago, during the eocene epoch, the region reached an average annual temperature of 10–20 °C (50–68 °F). The surface waters of the Arctic Ocean warmed enough to support tropical lifeforms.

paragraphs: Endangered marine species in the Arctic Ocean include walruses and whales. The area has a fragile ecosystem. The Arctic Ocean has relatively little plant life except for phytoplankton. Phytoplankton are a crucial part of the ocean. They feed on nutrients from rivers and the currents of the Atlantic and Pacific oceans.


title: Inuit

paragraphs: The Inuit are one of many groups of First Nations who live in very cold places of northern Canada, Greenland, the Arctic, and Alaska.

paragraphs: They are sometimes called "Eskimos", a word which likely comes from the Algonquin language and may mean "eater of raw meat". Most Inuit prefer to be called by their own name, either the more general Inuit particularly in Canada or their actual tribe name. Inuit is a tribe name but not all indigenous Arctic peoples in North America are Inuits. Particularly in the United States Alaska, the word Eskimo would be accepted as a more general term, but would probably refer to themselves by their tribe name.

paragraphs: Inuit in Canada and Greenland like the name "Inuit" because it is their own name for themselves. "Inuit" means more than one, one person is an ""Inuk"". The native Greenlanders are related to the Inuit. The language of the Inuit is Inuktitut, and it is one of the official languages of Nunavut and of the Northwest Territories in Canada. Eskimo is a term more frequently used in mainstream United States where such concerns get less attention.

paragraphs: Inuits in Alaska have various concerns, such as protecting the caribou from American oil pipelines. Anti-seal hunt campaigns work to eliminate this aspect of northern culture, which most Inuits regard as vital to their lives.

paragraphs: Inuit ate both raw and cooked meat and fish, as well as the fetus's of pregnant animals. Whale blubber was burned as fuel for cooking and lamps.

paragraphs: Inuit were also Nomadic people, but they did not domesticate any animals except for dogs, which they used to pull their sleds and help with the hunting. They were hunter-gatherers, living off the land. They were very careful to make good use of every part of the animals they killed. Respect for the land and the animals they harvested was and is a focal part of their culture.

paragraphs: Inuit lived in tents made of animal skins during the summer. In the winter they lived in sod houses and igloos. They could build an igloo out of snow bricks in just a couple of hours. Snow is full of air spaces, which helps it hold in warmth. With just a blubber lamp for heat, an igloo could be warmer than the air outside. The Inuit made very clever things from the bones, antlers, and wood they had. They invented the harpoon, which was used to hunt seals and whales. They built boats from wood or bone covered with animal skins. They invented the "kayak" for one man to use for hunting the ocean and among the pack ice.

paragraphs: Inuit sleds could be built from wood, bone, or even animal skins wrapped around frozen fish. Dishes were made from carving soapstone, bones, or musk ox horns. They wore two layers of skins, one fur side in, the other facing out, to stay warm.

paragraphs: Inuit had to be good hunters to survive. When an animal was killed in a hunt, it was thanked respectfully for offering itself to the hunter. They believed it intended to provide itself as a gift towards the survival of the hunter and his children. Their gratitude was deeply sincere and is an important aspect of their belief system. In the winter, seals did not come out onto the ice. They only came up for air at holes they chewed in the ice. Inuit would use their dogs to find the air holes, then wait patiently until the seal came back to breathe and kill it with a harpoon. In the summer, the seals would lie out on the ice enjoying the sun. The hunter would have to slowly creep up on a seal to kill it. The Inuit would use their dogs and spears to hunt polar bears, musk ox, and caribou. Sometimes they would kill caribou from their boats as the animals crossed the rivers on their migration.

paragraphs: The Inuit even hunted whales. From their boat, they would throw harpoons that were attached to floats made of inflated seal skins. The whale would grow tired from dragging the floats under the water. When it slowed down and came up to the surface, the Inuit could keep hitting it with more harpoons or spears until it died. Whale blubber provide Vitamin D and Omegas to their cultural diet, and prevented rickets. The whaling industry around the world has depleted the whale population, and now traditional whale hunting for subsistence purposes is rare around the world. Inuits have added to their modern northern diet with grocery foods, which are normally very expensive in the north.

paragraphs: During the summer months, the Inuit were able to gather berries and roots to eat. They also collected grass to line their boots or make baskets. Often the food they found or killed during the summer was put into a "cache" for use during the long winter. A cache was created by digging down to the permafrost and building a rock lined pit there. The top would be covered with a pile of rocks to keep out the animals. It was as good as a freezer, because the food would stay frozen there until the family needed it. Inuit cultural traditions and traditional stories provided each new generation with the lifeskills and knowledge to survive their environment and work together. They usually moved around in small groups looking for food, and sometimes they would get together with other groups to hunt for larger animals such as whales. The men did the hunting and home building, and also made weapons, sleds, and boats. The women cooked, made the clothes, and took care of the children. Children and infants under the ages of 5 became easy victims of hypothermia, and if they were to die, their mothers would weight the children's corpses with stones and wrap them in fishnets before placing the bodies through holes in the ice. The mothers believed the children's souls were being offered to the god Phallus, who would reincarnate them as whales. Something wrong here Phallus isn't found in North America. Some Canadian companies like Canada Goose and Moose Knuckle have clothing designs based on Inuit culture.

paragraphs: Today, most Inuit live in modern houses. Many still hunt or fish for a major part of their food supply and sometimes some income. Seal pelts are used to protect from the extreme cold in the Arctic and are far more effective than man-made fabrics. The technology has worked well for many thousands of years. Besides, commercial winter clothes are expensive. Today, they use rifles and snowmobiles when hunting, however traditional values respecting the animals hunted still very much applies. In Alaska, many of the people have received money from the oil discovered in that state on their traditional lands.

paragraphs: The Arctic is very different from the rest of the world. The way of life in the south does not work well in the north. Canada values having Inuit peoples in Canada's northernmost lands as proof of sovereignty over the Canadian portion of the Arctic Circle. It's a very challenging living in an Arctic environment. There is some controversy over the practice of sinking the corpses of child victims of hypothermia under the ice, as bodies have been known to drift through the currents and wash up on the eastern coast of Canada, and, upon occasion, the northeastern United States.


title: Basket

paragraphs: A basket is a container. It is usually light.

paragraphs: 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.

paragraphs: 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.

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


title: Software

paragraphs: 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.

paragraphs: 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.

paragraphs: 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.

paragraphs: 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.

paragraphs: The different types of software can be put into categories based on common function, type, or field of use. There are three broad classifications:


title: Container

paragraphs: A container is an object used for holding something. People put things in a container. The use of shipping containers is called Containerization.


title: South America

paragraphs: South America is the continent to the south of North America. These two continents are separated by the Panama Canal.

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

paragraphs: 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.

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


title: Bed

paragraphs: 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.

paragraphs: Prehistoric people used naturally material, such as piles of straw or leaves, to sleep on. Beds similar to ones used today were probably invented before the 4th millennium BC. Mattresses stuffed with feathers were first used in Ancient Rome.

paragraphs: 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.


title: Asia

paragraphs: Asia is the largest continent on Earth. It is in the northern hemisphere. Asia is connected to Europe in the west (creating a supercontinent called Eurasia). 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 and Cyprus are partly in other continents.

paragraphs: The Asian continent is the largest of all continents. 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.

paragraphs: 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.

paragraphs: Some countries are variously located in both Europe and Asia. Namely: Russia, Georgia, Kazakhstan, Cyprus and Turkey.

paragraphs: The Sinai Peninsula of Egypt lies in Western Asia, with the rest of the country lying in North-East Africa.


title: Wall

paragraphs: 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.

paragraphs: 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.

paragraphs: 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.

paragraphs: 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.

paragraphs: 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.

paragraphs: 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.

paragraphs: 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.

paragraphs: Cavity Wall consists of two separate wythes. The wythes are made of masonry. Those two walls are known as internal leaf and external leaf. This wall is also known as a hollow wall. It reduce weights on the foundation. It acts as good sound insulation.

paragraphs: 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.


title: Coordinated Universal Time

paragraphs: 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.

paragraphs: 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.

paragraphs: 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).

paragraphs: 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).

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

paragraphs: 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.

paragraphs: When this page loaded, it was , 2021 12, 22:12:48 in UTC.


title: Television

paragraphs: 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").

paragraphs: 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.

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

paragraphs: 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.

paragraphs: 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.

paragraphs: 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.

paragraphs: 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.

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


title: Sociology

paragraphs: Sociology is the study of societies and how humans act in groups. Sociology is a social science. People who study sociology are called sociologists. A society is the community of people living in a particular country or region and having shared customs, laws, and organizations.

paragraphs: Emmanuel-Joseph Sieyès in 1780 was first to use the term. The problems caused by the change to an industrial society, where many people moved to cities and worked in factories, were an early focus of sociology. Auguste Comte, Max Weber and Émile Durkheim were leading figures in the study of social phenomena. Themes included: community, authority, status, alienation and lack of power.

paragraphs: In the 2000s, some sociologists look at such things as: race, ethnicity, class, gender, the family and social interaction. They also study the breakdown of social structures; crime and divorce.

paragraphs: Sociologists research the structures that organize society, such as race, gender (whether a person is male or female), and social classes (rich or poor). They study the family and examine problems such as crime and drug abuse.

paragraphs: Most sociologists work in one or more specialty areas or "sub-fields". Sociology includes many sub-fields that examine different aspects of society. For example, social stratification studies inequality and class structure in society. The field of demography studies changes in population size or type. The field of criminology examines criminal behavior and crime. Political sociology studies government and laws. Sociology of race and sociology of gender examine how people think about race and gender.

paragraphs: Many sociologists also do research outside of the university. Their research is supposedly intended to help teachers, lawmakers, and government administrators to make better institutions, government programs, and rules.

paragraphs: Sociologists often use statistics to count and measure patterns in how people act or behave. Sociologists also interview people or hold group discussions to find out why people behave in certain ways. Some sociologists combine different research methods.

paragraphs: Social analysis has been done since the time of Plato. Sociology became accepted as a type of science in the early 1800s. European cities were changing as many people moved into cities and began working in factories. Sociologists tried to understand how people interacted and how groups interacted.

paragraphs: The word "sociology" was invented by French thinker Emmanuel-Joseph Sieyès in 1780. Early thinkers who wrote about sociology included Auguste Comte and Max Weber.

paragraphs: Sociology was taught in a university for the first time at the University of Kansas in 1890. The first European department of sociology was founded in 1895 at the University of Bordeaux by Émile Durkheim. The first sociology department to be established in Britain was at the London School of Economics and Political Science in 1904. In 1919 a sociology department was established in Germany at the Ludwig Maximilians University of Munich by Max Weber.


title: Sky

paragraphs: 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. The deepness of the blue increases as we look toward the horizon, and up to the point above us.

paragraphs: 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.

paragraphs: 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.

paragraphs: 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.


title: Tone language

paragraphs: 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.

paragraphs: Many Asian languages are tone languages, such as Chinese, Vietnamese, Thai, and Punjabi. Most languages, including Indo-European languages like English are not tone languages, but Punjabi is an exception. Moreover, many African languages like Yorùbá, Igbo, Luganda, and Zulu use tone as well.

paragraphs: 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. However, pitch accent is different from tones.

paragraphs: 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.

paragraphs: In Mandarin, the sentence "ma ma ma ma" () has four different words. If numbers identify the tones, they can be written "ma2 ma1 ma4 ma3", which means "the hemp's mother scolds the horse." Some ways of romanization mark each tone by a different spelling; "ma2 ma1 ma4 ma3" in Pinyin would be written "ma mha mah maa" in Gwoyeu Romatzyh. Most use numbers or accent marks ("mā má mǎ mà" in Pinyin). There is a passage called (). It has 92 characters; all read the same way in Mandarin ("shi") but with different tones.

paragraphs: 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:"

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

paragraphs: 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.

paragraphs: 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.


title: Dollar

paragraphs: 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: $.

paragraphs: 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, Indian rupee and Chinese Renminbi.


title: Beer

paragraphs: Beer is a type of alcoholic drink. It is made with water, hops, barley (types of cereal grains), and types of yeast (a fungus that produces alcohol). A process called fermentation turns sugar into alcohol, using yeast. Another product of the fermentation is carbon dioxide.

paragraphs: In general, all alcoholic drinks where yeast turns sugar into alcohol are called "beer". In these cases, distillation is not used. The difference to wine is that with wine, sugars from plants, such as fruit sugar, or that made by animals is used. As an example, mead is a wine made from honey. Japanese sake is made from rice, and uses yeast for fermentation; so even if some people call it "rice wine", sake is really a kind of beer.

paragraphs: The act of making beer is called "brewing". Beer is made by adding warm water to malted barley and other grains. The enzymes in the barley change the malted barley and other grains into simple sugars. This is called the mash. The water is then sparged (drained) from the grain. The water is now called wort. The wort is boiled and hops are added. Hops provide flavour and preserve the beer. After boiling the wort is cooled and yeast is added. The yeast turns the sugars into alcohol and the wort into beer.

paragraphs: Different beers can have different natures, depending on the ingredients used; for example, an ale uses top fermenting yeast. Top fermenting yeasts eat more sugar and produce more alcohol. A lager uses bottom fermenting yeast. Bottom fermenting yeasts eat less sugar and produce a crisper, cleaner taste. Adding hops makes the beer more bitter and aromatic. Specialty malts (different types of cooked barley) produce different flavours and colours. These flavours and colours are most notable in dark beers like Porter and Stout.

paragraphs: Different countries have different ways to make beer. In Germany, Austria, Switzerland, Czech Republic, and Slovakia, beer is usually made from just hops, malt, water, and yeast. This is because of the Reinheitsgebot. The Reinheitsgebot was a law that said says that beer can only be made from hops, malt, and water. Yeast was discovered after the Reinheitsgebot. The law was overturned by the European Union in 1992. In Belgium, however, beers have always been made with wheat, sugar, fruit, and other ingredients.

paragraphs: The type of yeast used determines the kind of beer made:

paragraphs: The earliest records of beer were written around 7000 years ago by the Sumerians. It is said that the Sumerians discovered the fermentation process by accident. It is not known exactly how this happened, but it could be that a piece of bread or grain became wet, and a short time later, it began to ferment and made a pulp that caused people to become drunk. A seal around 4,000 years old is a Sumerian "Hymn to Ninkasi", the goddess of brewing. This "hymn" is also a recipe for making beer. A description of the making of beer on this ancient engraving in the Sumerian language is the earliest account of what is easily recognised as barley, followed by a pictograph of bread being baked, crumbled into water to form a mash, and then made into a drink, that is recorded as having made people feel "...wonderful and blissful". It could even be possible that bread was first baked to be a way to make beer that is easy to carry around. The Sumerians were probably the first people to brew beer. They had found a "divine drink" -- they felt it was a gift from the gods.

paragraphs: "Normal" beers have around 3-5 % alcohol (for the volume, i.e. in 100ml beer there is 3-5ml alcohol). In brewing beer, the amount of alcohol can be made more or less quite easily. The Belgian types of beer are made by adding more sugar. Through the fermentation, this will then turn to alcohol. Today, there are beers with between 2% and about 16% of alcohol (about the same alcohol content as wine). Spirits can have up to 80% alcohol. Some beer labels say there is no alcohol in them because it was taken out later. This is not completely true, though. Beers "without alcohol" usually do have less than 1% of alcohol.


title: IP address

paragraphs: An IP address is a label which is used to identify one or more devices on a computer network, such as the internet. It can be compared to a postal address. An IP address is a long

paragraphs: number written in binary. Since such numbers are difficult to communicate, IP addresses are usually written as a set of numbers in a given order. Devices using IP addresses use the internet protocol to communicate.

paragraphs: The Internet Assigned Numbers Authority assigns IP addresses to regional internet registries (RIRs). The RIRs assign them to Internet Service Providers. Internet Service Providers then assign IP addresses to their customers. Very often, people have a router or gateway at home, to which they connect computers, printers, and other devices. These routers or gateways are often configured to assign "local" IP addresses to the devices that are connected.

paragraphs: Each address has two parts: One that specifies the computer or group of computers, and another which specifies the network. A device can have more than one IP address. Certain types of IP addresses are used to address a group of devices, while others are used to address only one device. Certain types of addresses are unique, others can be re-used. A number of IP addresses are used for special purposes, for example to obtain an IP address automatically.

paragraphs: An IP address is converted to physical or Media Access Control Address using the Address Resolution Protocol (ARP). If an IP address is your phone number, then your MAC address is your name. You may change your phone number, but your name will not change.

paragraphs: Suppose one of our friend wants to meet us but they don’t know our address. He asks for our address & then we give our address like 02, Vidyapuri Road, Supaul, Bihar, India. After giving the address, he or she can easily locate our address. The same thing is done in case of internet. Every network is assigned an address.

paragraphs: IANA (Internet Assigned Numbers Authority) allocates the IP address. IANA is responsible for the IP addressing system

paragraphs: An IP address is a long binary number, made of ones and zeros. An IPv4 address is 32 binary digits (or bits) long. An IPv6 is 128 bits long, allowing many more IP addresses to be used. IP addresses are usually written in human-readable form, where 8 bits are grouped into one octet. IPv4 addresses are usually written as a group of four numbers. Each number can take a value from 0 to 255. IPv6 addresses are written as a group of eight hexadecimal numbers. Many Ipv6 addresses contain many zeroes. There are special rules which say that in certain cases, these zeroes do not need to be written.

paragraphs: Certain IP addresses can be assigned freely on the local area network. Since they are not unique, they are not routed on the internet. The addresses which can be freely assigned are called private IP addresses, the ones which are unique are called public. To be routed, a private address needs to be translated into a public one. This process of translating between private and public addresses is called network address translation, or NAT. Routers and firewalls often also perform this task.

paragraphs: There are three different types of addresses:

paragraphs: There are different ways of getting a new IP address. One of them is called Bootstrap Protocol (usually shortened to BOOTP). The device that needs a new address, does not know what network it is in, so it uses an IP address of all zeroes (0.0.0.0) which it sends as a broadcast to the current network, on a special port. In addition, it sends the MAC address of the network card, plus a 4 byte random number. The BOOTP server will send a reply, also as broadcast, addressed to a different port. The reply will contain the mac address of the client, the random number, and the IP address of the client. When the client receives the data, it will set the address specified. If the BOOTP server is configured that way, it will also send the IP address and hostname of the BOOTP Server, the name and path to a file which should be loaded to boot the client (using TFTP) or the name of a directory, which the client should mount using NFS.

paragraphs: DHCP extends BOOTP, and allows to send more information, such as the address of a time server, or information which is useful for routing.

paragraphs: IP addresses obtained automatically can be dynamic or static. Static addressing means the same machine will always get the same IP address. With dynamic addresses, a device will get the next address which is not used. Dynamic addresses which are used need to be reviewed from time to time. If they are not renewed, they can be used for other devices.

paragraphs: With IPv4, each address consists of four 8-digit binary numbers, called octets. An IPv4 address is 32 bits in total. The biggest number one can make with 8 regular digits is 99,999,999, but the biggest number one can make with 8 binary digits is 255 (11111111 in binary), so each octet can be any number from 0 to 255.

paragraphs: An IPv4 address could look something like this:

paragraphs: Each octet is converted to its decimal form and separated by a period.

paragraphs: Also, there are special meanings associated with two different ending numbers. In general, a last number of 0 stands for the network (called "base address"), and a last number of 255 stands for all hosts on that network (called "broadcast address"). Computers that are on the same local network share 3 of the 4 numbers. A computer can be on more than one network. It can also have several names.

paragraphs: The problem with IPv4 is that it only allows for 4.3 billion addresses, and we've almost used them all. To delay this, Network Address Translation (NAT) was created. Network Address Translation has a network share one "public" IP address and give every computer on the network a "private" IP address. Everyone living in the same house uses the same address, but mail can be meant for multiple different people living in the house.

paragraphs: There are some IP addresses that are reserved for special purposes. For example, the address "127.0.0.1" is called the Loopback Address and will "loop back" any packets sent to this address back to the computer that sent them, like sending mail to yourself. Although this may not seem useful, it is used to test servers.

paragraphs: It may define as the it identifies the class of network

paragraphs: It may be define as the it identifies the host on network

paragraphs: It is a permanent internet address. It can’t be changed in this we have to configure manually. It is used in smaller network all server uses static IP’s. It is a simple way for Communication.

paragraphs: It is a temporary internet address. It assigned by a DHCP (Dynamic Host Configuration Protocol) server from a specific range of IP address.

paragraphs: To make a network work faster, it is split up into subnets. To do this, an IP address contains a "network" ID, "subnet" ID, and a "host" ID. A special binary number called a Subnet Mask is used to determine the size of the network, subnet, and host IDs.

paragraphs: The original IPv4 only supported 254 networks, so in 1981 the Internet addressing specification was changed to a classful network architecture. Classful network design allowed for a larger number of individual networks. The first three bits of an IP address determined its "class". Three classes ("A", "B", and "C") were defined for normal computer communication (Unicast). The size of the network ID was based on the class of the IP address. Each class used more octets for the network ID, making the host ID smaller and reducing the number of possible hosts.

paragraphs: Classful networks have been replaced by Classless Inter-Domain Routing (CIDR) since 1993. CIDR also provides a network address and host address. CIDR does not have classes, which means network and host address sizes don't have to be in octets.

paragraphs: An IPv4 Address in CIDR notation looks like192.168.0.14/24The slash and number represent the amount of bits that the network id uses, in this case 24 or 3 octets.

paragraphs: Because IPv4 is only 32 bits, the number of available addresses will run out. To prevent this, an organization called the Institute of Electrical and Electronics Engineers (IEEE) created IP Version 6 (IPv6), which will eventually finish replacing IPv4.

paragraphs: IP Version 6 uses 16 octets, or 128 bits in total. Octets in IPv6 are written in hexadecimal, and separated by colons (:). An IPv6 address might look like this:

paragraphs: An IPv6 address can be long and this can lead to mistakes when typing them into the computer or writing them down. There are two ways in which an IPv6 address can be made shorter without leaving anything out:

paragraphs: It is also called service server. It is based on client server network architecture. It contain a database of public IP address. DNS is being like a phonebook.

paragraphs: Versions before IPv4 were experimental and never widely used. Version 5 was used exclusively for the , which was also never widely used.


title: Eurasia

paragraphs: Eurasia is the combined landmass of the continent of Europe and Asia in the northern part of the Earth. Eurasia is made of Europe and Asia, which are on the same tectonic plate and do not have a sea between them. The word is made by adding "Eur" (from "Eur"ope) to "Asia" to make "Eurasia".

paragraphs: Some geographers say it's all one continent, because unlike the Americas or Africa, Europe and Asia are not divided by sea. The Ancient Greeks divided the world they knew into Europe, Asia and Africa. Knowing little of the land north of the Black Sea, they took that and the Sea of Marmara as dividing Europe from Asia. Since then, people have been talking about Asia and Europe as two continents so it is now a tradition.

paragraphs: The OECD’s Eurasia activities involve 13 countries extending from the borders of the European Union to the Far East:

paragraphs: Some other continents are not completely divided by sea and are joined together and by a thin strip of land (called an isthmus) like North America and South America. However, Europe and Asia are not divided by sea.

paragraphs: Sometimes Eurasia is divided into West Eurasia and East Eurasia. West Eurasia is Europe and the Middle East. Historians sometimes add North Africa to West Eurasia because the Sahara Desert divides North Africa from the other parts of Africa and it is as difficult to cross as a sea. It is the largest continent, and some people like to combine it with Africa as "Afro-Eurasia".


title: North Pole

paragraphs: 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.

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

paragraphs: 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.


title: Plural

paragraphs: 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.).

paragraphs: 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 "cats" is plural).

paragraphs: It is fair to say that most native English speakers do make mistakes in this area: it is one of the more troublesome aspects of the English language.

paragraphs: All European languages have plural forms. The suffix that is used in each one of these other languages is different from the suffix that is applied to English nouns.

paragraphs: In other languages, such as Chinese, Korean and Japanese, there is usually no plural ending.


title: Alexander Gode

paragraphs: Alexander Gottfried Friedrich Gode-von-Aesch or simply Alexander Gode (October 30, 1906 - August 10, 1970) a German-American linguist and translator. He helped create Interlingua.


title: Oceania

paragraphs: Oceania is a name used in geography for the region made up of Australia, New Zealand, New Guinea, and several other island nations in the surrounding area. Some people call this part of the world Australasia instead.

paragraphs: The term "Oceania" does not have one single agreed definition. In politics (United Nations etc.), it includes Australia and the nations of the Pacific from Papua New Guinea east, but not the Malay Archipelago or Indonesian New Guinea.

paragraphs: The widest definition of Oceania includes the entire region between continental Asia and the Americas, including 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.

paragraphs: Sometimes, people use the term 'Oceania' to include only the Polynesian and Melanesian islands in the Pacific Ocean, as separate from Australasia.

paragraphs: 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. This is known as the Wallace Line, after Alfred Russel Wallace.

paragraphs: samoa, fiji, vanuatu, tonga, kiribati, cook islands and others are part of the pacific islands which are located in Oceania


title: Southern Ocean

paragraphs: 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.

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


title: Catalan language

paragraphs: 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.

paragraphs: 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.

paragraphs: 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.


title: Corset

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


title: Pop music

paragraphs: Modern pop music grew out of 1950s rock and roll, (for example Chuck Berry, Bo Diddley and Little Richard) and rockabilly (for example Elvis Presley and Buddy Holly). In the 1960s, The Beatles became a famous pop music group. In the 1970s, other styles of music were mixed with pop music, such as funk and soul music. Pop music generally has a heavy (strong) beat, so that it is good for dancing. Pop singers normally sing with microphones that are plugged into an amplifier and a loudspeaker.

paragraphs: There are also many more people working on pop music who are not seen on the stage or in the video. These people include the studio staff (people who help the musicians to record CDs and music videos in music studios), production staff (people who help make the music recordings sound good), distribution staff (people who help sell the music to stores) and retail staff (people that sell the music to people at CD stores).

paragraphs: Tour staff help the band to travel around the country (or around the world) for their concert tours. Some tour staff help by carrying heavy musical instruments onto the stage. Other tour staff drive buses or cars, so that the band can get to the concert. Some tour staff operate sound equipment, such as the large amplifiers and loudspeakers that are used to amplify (make louder) the band's music for the audience.

paragraphs: Promotional staff help to market or promote the band's music, so that more people will know about the band, and buy the band's CDs. Some promotional staff travel to radio stations and give the band's CD to radio station managers or DJs (disk jockeys: the people who announce songs on the radio). Other promotional staff write press releases (short articles) about the band which are sent to the newspapers.

paragraphs: Pop music came from the Rock and Roll movement of the early 1950s, when record companies recorded songs that they thought that teenagers would like. Pop music usually uses musical from the other types of music that are popular at the time. Many different styles of music have become pop music during different time periods. Often, music companies create pop music styles by taking a style of music that only a small number of people were listening to, and then making that music more popular by marketing it to teenagers and young adults.

paragraphs: In the 1950s, recording companies took blues-influenced rock and roll (for example Chuck Berry and Bo Diddley) and rockabilly (for example Carl Perkins and Buddy Holly) and promoted them as pop music. In the late 1960s and early 1970s, record companies took folk music bands and musicians and helped them to create a new type of music called folk rock or acid rock. Folk rock and acid rock mixed folk music, blues and rock and roll (for example The Byrds and Janis Joplin). In the 1970s, record companies created several harder, louder type of blues called blues rock or heavy metal, which became a type of pop music (for example the bands Led Zeppelin and Judas Priest).

paragraphs: In the late 1970s and early 1980s, a type of nightclub dance music called Disco turned into a popular type of pop music. Record companies took an experimental, strange-sounding type of music called New Wave music from the 1980s and turned it into pop music bands such as "The Cars." In the 1990s record companies took an underground type of hard rock called Grunge (for example the band Nirvana). Michael Jackson was also a very influential artist for pop music. His album, "Thriller", is the best-selling album of all time. He also wrote some other very influential songs, such as "Bad", "Give In to Me", "Will You Be There", "Heal the World", "We Are the World", "Black or White", and "Billie Jean", just to name a few. By the 21st century (after the demise of disco in the 1980s) Contemporary R&B became pop music. Examples of Contemporary R&B artists that have a wide pop appeal are Usher, Beyoncé, Rihanna, Chris Brown and more. Pop rappers Flo Rida and Kesha were mainstream in the late 2000s and the early 2010s. Modern pop singers include Ariana Grande, Katy Perry and Lady Gaga. Nicki Minaj blended pop and hip hop in the early 2010s.


title: General semantics

paragraphs: General semantics is a philosophy that deals with how people react to things that happen around them based on meaning. It was created by Alfred Korzybski during the 1920s and early 1930s.

paragraphs: The goal of general semantics is for people to know that when we simplify something, either mentally or in language, that simplification is not the same thing as the thing simplified. How people understand reality is not the same as what reality is because people do not know everything about reality. General semantics teaches that there is always more to something than what is seen, heard, felt, or believed.


title: Semiotics

paragraphs: 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.

paragraphs: Semiotics is usually divided into three parts:

paragraphs: The major branches of semiotics include:


title: Nitrogen

paragraphs: Nitrogen is a nonmetal chemical element. The atmosphere contains more than 78 percent of nitrogen. It has the chemical symbol N and atomic number 7. Its stable inside typically contains 14 nucleons (7 protons and 7 neutrons). It has 5 electrons in its outer shell.

paragraphs: Nitrogen is a colorless odorless gas at normal temperature. It is normally attached to another nitrogen atom, making a nitrogen molecule (N). This bond is very strong. That is why many explosives contain nitrogen. The bond is broken when the explosive is made. When it explodes the bond forms, releasing a lot of energy.

paragraphs: It turns into a liquid at -195.8°C and turns into a solid at -210°C. If it is compressed, it can be turned into a liquid without making it cold.

paragraphs: It usually does not combine with other atoms because its strong bond prevents it from reacting. Lithium is one of the few chemical elements that react with nitrogen without being heated. Magnesium can burn in nitrogen. Nitrogen also makes blue electric sparks. The blue color is caused by the atoms being excited. When they get normal again, they release light. When nitrogen is excited, it reacts with many things that it does not normally react with.

paragraphs: Many chemical compounds that are important for industrial purposes contain nitrogen ions. These include ammonia, nitric acid, nitrates and cyanides. Nitrogen comes in several oxidation states; -3, -2, -/, +1, +3, +4, and +5. Each of those oxidation states has its set of compounds.

paragraphs: Compounds in the -3 oxidation state are weak reducing agents. These include ammonia, ammonium, amide and nitrides. Amino acids and proteins contain nitrogen in this oxidation state. Hydrazine, a compound in the -2 oxidation state, is a strong reducing agent. Azides contain nitrogen in the -/ oxidation state. They are extremely powerful reducing agents, and most are very toxic.

paragraphs: Nitrous oxide contains nitrogen in the +1 oxidation state. It is used as an anesthetic. Compounds containing nitrogen in the +2 oxidation state, such as nitric oxide, are reducing agents. +3 oxidation state compounds are strong oxidizing agents and weak reducing agents. Nitrites are the most common +3 compounds. Compounds in the +4 oxidation state are strong oxidizing agents. They include nitrogen dioxide and dinitrogen tetroxide.

paragraphs: Compounds containing nitrogen in the +5 oxidation state are strong oxidizing agents. They are one of the more common groups of nitrogen compounds. They include nitric acid and dinitrogen pentoxide. They also include nitrates, which are used in explosives such as dynamite, nitroglycerin and trinitrotoluene.

paragraphs: Air is made up of about 78% nitrogen and about 20.95% oxygen, < 1% argon, and traces of other gasses such as carbon dioxide, and water vapor, among others. It is also in a few nitrates in the ground. Ammonium minerals are rare. Nitrogen is in proteins.

paragraphs: Pure liquid nitrogen can be made by cooling air. The nitrogen turns into a liquid at a different temperature than the oxygen. It can also be made by heating certain chemical compounds, such as sodium azide.

paragraphs: Nitrogen as an element is used to prevent things from reacting with the oxygen in the air. It can be used to fill crisp bags and incandescent bulbs. It is also used to fill some tires. It can be used to make electric components like transistors. Liquid nitrogen can be used to freeze things.

paragraphs: Nitrogen compounds have many uses, such as anesthetics (nitrous oxide), explosives (dynamite), cleaners (ammonia), and meat (protein), and planes (fuel).

paragraphs: Oil companies use high pressure nitrogen to help force crude oil to the surface.

paragraphs: Nitrogen was discovered by Daniel Rutherford in 1772, who called it "noxious gas" or "fixed gas". They discovered that part of air did not burn. It was found that animals died in it. It was known as "azote". Many nitrogen compounds also contain the "azide" or "azine" letters, such as hydrazine.

paragraphs: In 1910, Lord Rayleigh found out that when a spark was passed through nitrogen, it made a reactive form of nitrogen. This nitrogen reacted with many metals and compounds.