AcharyaChanakya/simple-wikipedia huggingface dataset:
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.
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.
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.
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.
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.
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.
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.
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".
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.
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.
The Indian Ocean is the ocean surrounded by Asia to the north, Australia and the Pacific Ocean to the east, the Southern Ocean to the south, and Africa and the Atlantic Ocean to the west. It is named for the river Indus and Ancient India on its north shore. The Bay of Bengal, the Arabian Sea, the Persian Gulf and the Red Sea are all parts of this ocean.
The deepest point in the Indian Ocean is in the Java Trench near the Sunda Islands in the east, 7500 m (25,344 feet) deep. The average depth is 3,890 m (12,762 ft). The Indian Ocean is the third largest ocean, 28,350,000 square miles in size. The majority is in the southern hemisphere.
Arctic Ocean
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.
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.
The average depth of the Arctic Ocean is . The deepest point is in the Eurasian Basin, at .
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.
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.
Countries bordering the Arctic Ocean are: Russia, Norway, Iceland, Greenland, Canada and the United States.
The Arctic Ocean is in a polar climate. Winters are characterized by the polar night, cold and stable weather conditions, and clear skies.
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.
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).
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.
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.
The Inuit are one of many groups of First Nations who live in very cold places of northern Canada, Greenland, the Arctic, and Alaska.
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.
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.
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.
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.
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.
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.
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.
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.
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.
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.
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.
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.
A basket is a container. It is usually light.
Basket makers use a wide variety of materials to create a basket, such as bark, willow rods, leaves, wire, plastic, paper, and rope. There are three basic kinds of baskets—coiled, twined, or woven. A woven basket is made of spokes and weavers: the spokes run up and down and the weavers go over and under the spokes. A coiled basket is made by sewing rings of a fibrous material to the previous ring. Twined baskets have flexible weavers that are twined around the spokes in a variety of patterns.
Basketmaking is so old that it features in myths from various cultures. Baskets are used to carry babies, plants, fruit, cotton, and Easter eggs. Coroners once used a basket coffin to collect bodies, thus the expression "a basket case" which meant the person was dead.
In basketball, the basket is an open net fixed to a metal ring in which players try to throw the ball.
Computer software, also called software, is a set of instructions and documentation that tells a computer what to do or how to perform a task. Software includes all different programs on a computer, such as applications and the operating system. Applications are programs that are designed to perform a specific operation, such as a game or a word processor. The operating system (e.g. Mac OS, Microsoft Windows, Android and various Linux distributions) is a type of software that is used as a platform for running the applications, and controls all user interface tools including display and the keyboard.
The word software was first used in the late 1960s to emphasize on its difference from computer hardware, which can be physically observed by the user. Software is a set of instructions that the computer follows. Before compact discs (CDs) or development of the Internet age, software was used on various computer data storage media tools like paper punch cards, magnetic discs or magnetic tapes.
The word firmware is sometimes used to describe a style of software that is made specifically for a particular type of computer or an electronic device and is usually stored on a Flash memory or ROM chip in the computer. Firmware usually refers to a piece of software that directly controls a piece of hardware. The firmware for a CD drive or the firmware for a modem are examples of firmware implementation.
Today, software has become an important part of our lives. software is used everywhere. software engineers are responsible for producing fault-free software which has literally become an essential part of our daily lives. Changeability and conformity are two of the main properties of software design. There are also different processing models for designing software including Build and Fix, Waterfall and Agile software processing design methods.
The different types of software can be put into categories based on common function, type, or field of use. There are three broad classifications:
South America is the continent to the south of North America. These two continents are separated by the Panama Canal. There are seven continents which make up the globe, South America being the 4th largest.South America includes 14 countries: Argentina, Bolivia, Brazil, Chile, Colombia, Ecuador, Falkland Islands (United Kingdom), French Guiana (France), Guyana, Paraguay, Peru, Suriname, Uruguay and Venezuela.
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.
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.
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.
The most popular attractions are:
The amazon rain forest is a moist grassy land where many wild animals live and contains the amazon river which is the 2nd longest river in the world and and has the largest volume of water.The world's longest river is the Nile in Africa. The forest is known as a rain forest as it rains very often but due to the dense surroundings not every droplet reaches the bottom. The Amazon is shared by eight countries (Brazil, Bolivia, Peru, Ecuador, Colombia, Venezuela, Guyana and Suriname) and stretches for 6.7 million kilometers2. In the amazon rain forest, hundreds of thousands of trees have been cut down for wood and paper,meaning that the forest is endangered. Unlike the Boreial forest in Canada the trees are not getting replanted.
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.
In August 2020 archaeologists reported the discovery of the oldest grass bedding from Middle Paleolithic (at least 200,000 years ago). This was much older than the oldest previously known bedding.
They found insect-repellent plants and ash layers beneath the bedding. This would have made a dirt-free, insulated base which helped to keep away insects. So early beds were little more than piles of straw or some other natural material (e.g. a heap of palm leaves, animal skins, or dried ferns).
Here's an example of what they said: "Several cultures have used ash as an insect repellent because insects cannot easily move through fine powder. Ash blocks insects' breathing and biting apparatus, and eventually dehydrates them. "Tarchonanthus" (camphor bush) remains were on top of the grass from the oldest bedding in the cave. This plant is still used to deter insects in rural parts of East Africa".
Mattresses stuffed with feathers were first used in Ancient Rome.
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.
Asia is a large region on Earth mainly in the northern hemisphere. Asia is connected to Europe in the west, forming a continent called Eurasia, though sometimes it is viewed as a separate continent from Europe. Some of the oldest human civilizations began in Asia, such as Sumer, China, and India. Asia was also home to some large empires such as the Persian Empire, the Mughal Empire, the Mongol Empire, and the Ming Empire. It is home to at least 44 countries. Turkey, Russia, Georgia and Cyprus are partly in other continents.
Asia includes a large amount of land. Covering about 30% of the world's land area, it has more people than any other continent, with about 60% of the world's total population. Stretching from the icy Arctic in the north to the hot and steamy equatorial lands in the south, Asia contains huge, empty deserts, as well as some of the world's highest mountains and longest rivers.
Asia is surrounded by the Mediterranean Sea, the Black Sea, the Arctic Ocean, the Pacific Ocean, and the Indian Ocean. It is separated from Europe by the Pontic Mountains and the Turkish Straits. A long, mainly land border in the west separates Europe and Asia. This line runs North-South down the Ural Mountains in Russia, along the Ural River to the Caspian Sea, and through the Caucasus Mountains to the Black Sea.
Some countries are variously located in both Europe and Asia, namely Russia, Georgia, Kazakhstan, Cyprus, and Turkey.
The Sinai Peninsula of Egypt lies in the Arabian peninsula, with the rest of the country lying in North-East Africa.
Before powerful artillery was invented, many cities had protective walls. Since they are not suitable for defense any more, most city walls have been removed.
The term "the Wall" usually referred to the Berlin Wall, built during the Cold War, which fell in 1989, but may also refer to the Pink Floyd album of the same name.
A retaining wall is a structure made to hold soil from collapsing. It is made in special areas for any other construction work, such as farming or road making.
Types of retaining wall are:
Load Bearing Wall is a structural element. It carries the weight of a house from the roof and upper floors, all the way to the foundation. It supports structural members like beams, slab and walls on above floors.
Non-Load Bearing Wall doesn’t help the structure to stand up and holds up only itself. It doesn’t support floor roof loads above. It is a framed structure. Most are interior walls whose purpose is to divide the structure into rooms.
Partition Wall separates spaces from buildings. It can be solid, constructed from brick or stone. It is a framed construction. The partition wall is secured to the floor, ceiling, and walls. It is enough strong to carry its own load. It resists impact. It is stable and strong to support wall fixtures. The partition wall works as a sound barrier and it is fire resistant.
Cavity Wall A cavity wall or hollow wall consists of two separate walls, called leaves or skins, with a cavity or gap in-between. The two leaves of the cavity wall may be of equal thickness if it a non-load-bearing wall or the internal leaf may be thicker than the external leaf, to meet the structural requirements.
Veneered Wall holds up the material. It can be made of brick or stone. The most famous veneered wall is made of brick. The wall is only one wythe thick. It became the norm when building codes began to require insulation in interior walls. It is light weighted. Veneered walls can be built quickly.
Coordinated Universal Time (or UTC) is the standard time system of the world. It is the standard by which the world regulates clocks and time. It is, within about 1 second, mean solar time at 0° longitude.
The standard before was Greenwich Mean Time (GMT). UTC and GMT are almost the same. In fact, there is no practical difference which would be noticed by ordinary people.
Some websites, for example Wikipedia, use UTC because it does not make any country look more important than the others. It offers one time for all the Internet (the same time can be used by people all over the world).
Time zones are often named by how many hours they are different from UTC time. For example, UTC−5 (United States east coast) is 5 hours behind UTC. If the time is 07:00 UTC, the local time is 02:00 in New York (UTC−5) and 10:00 in Moscow (UTC+3).
07:00 UTC is also written more simply as 0700Z (or 07:00Z).
Note that UTC uses the 24-hour clock. That means there is no 'AM' or 'PM'. For example, 4:00PM would be 16:00 or 1600.
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Telegram television (also known as a TV) is a machine with a screen. Televisions receive broadcasting signals and change them into pictures and sound. The word "television" comes from the words tele (Greek for "far away") and vision ("sight").
Sometimes a television can look like a box. Older TVs had a large cathode ray tube in a large wooden frame and sat on the floor like furniture. Newer TVs are much lighter and flatter.
A TV can show pictures from many television networks. Computers and mobile devices also can be used for watching television programs.
The television was invented in the 1920s but the equipment was expensive and the pictures were poor. By the 1950s, these problems had been fixed and TVs became widespread.
At first, all televisions used an antenna (or aerial). This would pick up television programmes from broadcasting stations. A TV station could be many miles or kilometers away, and still be received. TVs can also show movies from VCD and DVD players or VCRs. Cable TV and Satellite television can provide more programs at once than broadcast can. Video game consoles connect to most modern TVs. Some computers can also use a TV as a computer monitor.
All TVs have screens where the picture is viewed. Before the 1950s these were usually "black and white", which made everything look grey, but all modern TVs show colors. Most 20th century screens also had rounded corners. That is because television screens were cathode ray tubes. These are like heavy glass jars with one side bulging out to form the screen.
Today flat panel displays are the usual kind. These are usually flat rectangles with straight edges. This long rectangle looks more like the shape of a movie theatre screen. This is called widescreen. If a widescreen set was 30 cm tall, it would be 53 cm wide. For this to work best, TV shows also need to be made in widescreen. Widescreen sets can still be any size, but they have the same widescreen shape.
The early 21st century is also when digital television transmission became more common than analog television.
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.
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.
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.
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.
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. 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.
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.
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.
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.
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.
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.
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.
The sky, which is made up of gas molecules, is blue because of the random scattering of sunlight by the molecules. Rayleigh scattering defines the amount of scattering of light rays. Blue light scatters much more than red, which is why the sky appears blue on a clear day. Depending on the time of day, the sky may appear different colors. At dawn or dusk the sky may appear red, orange, or even green and purple depending on how low the sun is and how close it is to night.
Other planets have skies too. Because the types of gases in their atmospheres are different, they have different sky colors. For example, the sky on Mars is red.
Many things can be seen in the sky. There are objects from space like the Sun, Moon, and stars. There are also many weather events seen in the sky. For example, these can be clouds, rain, lightning, or fog. Weather is caused by different patterns and temperatures in the atmosphere. Other things that can be seen in the sky are birds, other flying animals, and aircraft.
Tone language
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.
About 70% of world languages in Asia, the Pacific, Africa, and the Americas are tonal, including Chinese, Vietnamese, Thai, Punjabi, Yorùbá, Igbo, Luganda, , and Cherokee. The other languages, including Indo-European languages such as English and Hindi, are not tone languages.
In some languages, it is pitch accent that is important instead. A word's meaning can then change if a different syllable is stressed. Examples include Ancient Greek, Hebrew, Swedish, Norwegian, Serbo-Croatian, Lithuanian, and some Asian languages like Japanese and Korean. However, pitch accent is different from tones.
Some tones may sound alike to people who do not speak a tone language. They are the most difficult part of learning a tone language for those people.
In Mandarin, the most famous example ""mā má mǎ mà" ()" has four different words each pronounced in exactly the same way but with four different tones. If numbers identify the tones, they can be written m"a1 ma2 ma3 ma4", which means "mom hemp horse scold." Some ways of romanization mark each tone by a different spelling; "ma1 ma2 ma3 ma4" in Pinyin would be written "ma mha maa mah" in Gwoyeu Romatzyh. Most use numbers or accent marks ("mā má mǎ mà" in Pinyin). There is a passage called (). It has 92 characters; all read the same way in Mandarin ("shi") but with different tones.
Mandarin does not have many syllables: the words for "mother," "hemp," "horse," "scold," and a word put at the end of sentences to make it a question are all pronounced "ma:"
Mandarin has "first tone," "second tone," "third tone," "fourth tone," and "neutral tone." Other Chinese dialects have more tones, some as many as twelve.
Vietnamese and Pinyin use accents as the tone marks for the Latin alphabet. Each accent shows an altered sound for the syllable. Most syllables have only one tone marking, but the letters in the syllable can be altered by other markings. Syllables usually form one word in un-hyphenated compound words.
Pinyin may have style differences because its use is to help Westerners. On the other hand, Vietnamese has a national script that always follows and uses the same style.
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: $.
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.
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.
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.
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.
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.
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.
The type of yeast used determines the kind of beer made:
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.
"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.
An IP address (short for Internet Protocol 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
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.
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.
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.
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.
Suppose one of our friends wants to meet us but they don’t know our address. He asks for our address and then we give our address (Example: 123 Main Street, Anytown, USA). 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.
IANA (Internet Assigned Numbers Authority) allocates the IP address. IANA is responsible for the IP addressing system.
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.
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, and 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.
There are three different types of addresses:
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.
DHCP extends BOOTP, and allows to send more information, such as the address of a time server, or information which is useful for routing.
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.
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.
An IPv4 address could look something like this:
Each octet is converted to its decimal form and separated by a period.
There are are also 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.
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.
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.
It identifies the class of a network.
It identifies the host on a network.
It is a permanent internet address. It has to be configured manually. It is used in smaller networks. All servers use static IP addresses. It is a simple way for communication.
It is a temporary internet address. It is assigned by a DHCP (Dynamic Host Configuration Protocol) server from a specific range of IP address.
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.
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.
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.
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.
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.
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:
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:
DNS stands for Domain Name System
It is also called a service server, and is based on client server network architecture. Like a phonebook, it contains a database of public IP addresses.
Versions before IPv4 were experimental and never widely used. Version 5 was used exclusively for the , which was also never widely used.
Eurasia is the combined landmass of Europe and Asia in the northern part of Earth. It has the Atlantic Ocean on its west, and the Pacific Ocean to the east. The Arctic Ocean is to its north, and the Mediterranean and Pacific Ocean to its south. It is the largest of the continents. Its name comes from adding the "Eur" from "Europe" to "Asia". It and Africa form a part of the world called "Afro-Eurasia".