cahya/simple-wikipedia huggingface dataset:
Rain is a kind of precipitation. Precipitation is any kind of water that falls from clouds in the sky, like rain, hail, sleet and snow. It is measured by a rain gauge. Rain is part of the water cycle.

Clouds will often absorb smoke to create rain, commonly referred to as "nature's laundry" due to this process.

Some places have frequent rain. This makes rainforests. Some have little rain. This makes deserts.

A rainstorm is a sudden heavy fall of rain. It may cause flash floods in valleys. Heavy rain for a long time may make floods that destroy houses and drown people. Also, landslides may happen.

Convectional rain 
When the Sun heats the Earth's surface, the ground heats the air above it. Convection makes the air rise and  cool. When it cools to the dew point, clouds form and rain follows.This usually occurs on flat land. This type of rainfall often causes summer showers and thunderstorms.

Relief rain 
Relief rain usually occurs along coastal areas where a line of hills runs along the coast. When wet onshore wind from the sea meets a mountain, hill or any other sort of barrier, it is forced to rise along the slope and cools. When the air temperature falls to its dew point, water vapour condenses to form clouds. When the clouds can no longer hold the water droplets, relief rain begins to fall on the windward slope of the mountain.  On the leeward slope, air sinks, it is warmed and further dried by compression. Therefore, the leeward slope is known as rain shadow. Moist winds blow in from the sea and are forced to rise over the land. The air cools and the water vapour condenses, forming rain drops. The rainiest places in the world are places that have relief rainfall.

Frontal rain/Cyclonic rain 

Frontal rain happens when cooler air and warmer, humid air meet in a weather front.  The less dense warm air rises and condenses forming clouds. These clouds grow and eventually create rain. In some places on the northern temperate zone the cold air front tends to come from the north west and the warm air front comes from the south west.

Collection 
Some people collect rain in a rainwater tank. People use rainwater for watering plants, cleaning the house, bathing, or drinking. It is not always safe to drink rainwater. It can have bacteria, parasites, viruses, and chemicals that could make people sick.

Related pages 
 Water cycle

References

Other websites 

BBC article on rain-making.

Basic English 850 words
Precipitation
Gambling is a contest where a player bets on the result of an event. The bet is generally in the form of money. The rules and the amount of money bet have to be decided on before the event happens.

History
Playing cards appeared in the 9th century AD in China. Records trace gambling in Japan back at least as far as the 14th century.

Poker, the most popular U.S. card game associated with gambling, derives from the Persian game As-Nas, dating back to the 17th century.

The first known casino, the Ridotto, started operating in 1638 in Venice, Italy.

Types
There are three variables common to all gambling.
 The amount of the bet.
 The predictability, or probability, of something that would happen in the event.
 The odds agreed upon by the players.

There are many types of gambling. Casino games, sports betting (especially horse racing), and state lotteries are some of the most common forms of gambling. Investments, such as stocks, bonds and real estate, are also sometimes considered forms of gambling. Generally, the odds are not in favor of the gambler.

Issues
Many people gamble for fun and entertainment. For others it becomes an addiction and a financial burden. Gambling addiction is a serious mental health issue that can become life-threatening. People with a gambling problem should seek help. Research shows that older people are more vulnerable and how the brain can get addicted to gambling.

Rules
Gambling regulation differs in different countries. Some have established specific legal institutions. However, some countries have only overseeing laws. A well-known executive institution is The Gambling Commission in the UK. Its main function is controlling commercial gambling in partnership with people in charge of licensing. An example of strict ruling is the Gambling Law in the USA. The law decides gaming rules for local, state, and federal businesses. In the United States, gambling is restricted almost everywhere, except in Las Vegas and in Atlantic City, New Jersey. New Jersey, legalised online gambling and poker in November 2013.In 2018, Swiss citizens voted that gambling should also be allowed on the Internet in the future. A convincing 73% voted in the referendum, in which 1.8 million Swiss people took part. The new Gaming Act was put into effect by the Federal Gaming Board on January 1, 2019. Since then, it has been completely legal for Swiss citizens to play games of chance on the Internet.

In some places, such as mainland China, gambling is illegal. Chinese people cannot do so inside their country, so they go outside of it, such as to Macau, which is known as the "gambling capital of the world" because of its many big casinos. Other countries and local governments, such as Hong Kong, have some kind of gambling control board to make sure people don't gamble too much while allowing them to gamble.

Gambling has been banned in Brazil since 1946.

References

Other websites
 Gambling legislation and regulations
Monty Python, also known as The Pythons, is a group of British comic actors. They have acted in several comedy movies (most famously, Monty Python and the Holy Grail). They had a television show, Monty Python's Flying Circus between 1969 and 1974, which is still well-known and watched around the world.

The members of Monty Python are: John Cleese, Eric Idle, Graham Chapman, Terry Gilliam, Terry Jones, and Michael Palin. Carol Cleveland and Neil Innes regularly appeared in their movies. 

Monty Python started with their first movie, And Now For Something Completely Different, and finished with their final movie, Monty Python's The Meaning of Life.

Movies
And Now For Something Completely Different (1971)
Monty Python and the Holy Grail (1975)
Monty Python's Life of Brian (1979)
Monty Python Live at the Hollywood Bowl (1982)
Monty Python's The Meaning of Life (1983)

Theatre
Monty Python's Flying Circus – Between 1974 and 1980 
Monty Python's Spamalot
Not the Messiah (He's a Very Naughty Boy)
Monty Python Live (Mostly)

Other websites
Time zones give specific areas on the Earth a time of day that is earlier or later than the neighboring time zones. This is because when it is daytime on one side of the earth, it is night-time on the other side. There are 24 time zones dividing the earth into different times, each with its own name, like the North American Eastern Time Zone. The North American Eastern Time Zone contains large cities in North America like New York City and Miami.

Greenwich Mean Time (GMT) began in 1675. This was when the Royal Observatory, Greenwich was built to help ships find their longitude at sea. GMT was a standard reference for time keeping when each city kept a different local time. When railways began carrying many people quickly among cities keeping different time, they adopted time zones to simplify operations. By about 1900, almost all time on earth was in the form of standard time zones. 

Greenwich Mean Time is now called UTC (Coordinated Universal Time). UTC is the time standard of the world. All other parts of the world are offset (plus or minus) according to their longitude. Most of the zones are offset by a full hour, but there are some offset by half an hour or 45 minutes.

In some parts of the world they follow the Daylight Saving Time (DST), and during this period of time in summer they add one hour to their normal solar hour.

In the poles, the time is UTC in the North Pole and UTC+12 in the South Pole.

The time zones are numbered in relation to the UTC, so in Los Angeles the time zone will be UTC−8, in London UTC+0, in Rome UTC+1, and in New Delhi UTC+5:30.
A market is a place where people go to buy or sell things. When people have products to sell, they set up a market place.  There may be a special building for the market place, or the market may be held in an open space where the sellers can put up a stall (like a kind of tent) and then take the stall down at the end of the day.

The word market can also have a more general meaning in the economy.  It can mean the way things are bought or sold.  "There is a big market for dishwashers" means that lots of people want to buy dishwashers, so therefore a business that makes dishwashers is likely to be able to make a lot of money.  When things are sold, people buy the product, and this "stimulates the economy" (helps people to spend and earn money). The market needs to balance supply and demand. There is no point in supplying (making) lots of dishwashers if people do not want them.  In the market prices may change quickly if supply or demand changes.

Competition 
If a seller of a good cannot supply what customers want or ask for too high of a price, other sellers may try to supply that good. If other sellers enter the market for that good, in competition, that will tend to fulfill demand and lower prices.  Sellers who do not like competition may try to kill the competition. This would establish a monopoly, and many countries have laws to protect the free market against such practices.

Related pages 
 Market forms
 Shop

Basic English 850 words
An ambassador is a person sent by the government of a country to a different country. The ambassador is the official representative of their country.  The ambassador speaks to officials of the other country about any problems and issues between the two countries.

In past years, communication between countries could take days or weeks. It was necessary to have a person in each foreign capital to have meetings and make negotiations between countries. Nowadays, communication is much faster, and often governments can be in direct contact with each other.  However, it is still true that many problems need person-to-person meetings, so ambassadors are still needed.

Often an ambassador will live in the foreign country for a number of years. An embassy is where the ambassador lives. Embassies are most often in the capital of the foreign country. An ambassador may bring people with him to help him and work at the embassy. Some of the high ranking people may be called embassy officials.

It is both tradition and law that the ambassador and many embassy officials have diplomatic immunity. They cannot be arrested or prosecuted in the foreign country. The only possibility is to send a person back to their own country.

Government occupations
Monday is a day of the week. In some countries, it is the second day of the week. In other parts of the world, including some countries in Europe, Monday is the first day of the week.

The International Standards Organization considers Monday the first day of the week.

Other websites

01
A nuclear war is a war in which countries fight with nuclear weapons. Because nuclear weapons are extremely powerful and could cause destruction throughout the world, the possibility of nuclear war has had a great effect on international politics.

So far, two nuclear weapons have been used during warfare. They were used in the atomic bombings of Hiroshima and Nagasaki and resulted in the deaths of approximately 120,000 people. Thousands of much more powerful bombs were made in later years.  They have not yet been used in war.

History 
Nuclear bombs were invented by the United States with Canadian and British help during World War II to help make that war stop.  The destruction of Hiroshima and Nagasaki and the Soviet invasion of Manchuria caused Japan to surrender.  They are still the only nuclear weapons that have ever been used in fighting a war.  At that time only the United States had the technology needed to make the bomb, but within a few years the Soviet Union had developed it too. In the new Cold War, the United States and the Soviet Union were enemies and each had many nuclear weapons, but they did not dare to use them against each other, either directly or by attacking the other country's allies. Since either country could be completely destroyed by the other's weapons, nuclear war could no longer be limited to the use of only one or two bombs; if they were used anywhere by one side, the other would attack with its own nuclear weapons, and the fighting would almost certainly become greater. This situation came to be known as the "balance of terror," or Mutually Assured Destruction, and stopped conflicts between the two superpowers from leading to a third world war.

Since the end of Communist rule in Russia and Eastern Europe, tensions between America and Russia have eased and war has become less likely. However, today there is more worry about nuclear proliferation. Countries around the world who already have their own bombs include Britain, France, China, Israel, India, Pakistan and North Korea; as all kinds of technology tend to become cheaper and easier to get and use, there is a fear that nuclear weapons could become available to countries with unstable governments. There is also the possibility that terrorists might be able to capture or build nuclear weapons and use them.

Nuclear war in fiction 

Ever since the end of World War II, writers, film-makers, and artists have created works of fiction imagining how a nuclear war might happen and what life would be like afterwards. Most have pictured widespread death and destruction, and a grim post-armageddon world where a few survivors struggle to live without power, medicine, or food. Some have pictured civilization breaking down completely, and primitive societies developing; with the past world becoming forgotten.

Related pages 
World War III

War
Nuclear weapons
Tax is money that people have to pay to the government.

The government uses the money it gets from taxes to pay for things. For example, taxes are used to pay for people who work for the government, such as the military and police, provide services such as education and health care, and to maintain or build things like roads, bridges and sewers.

Types of taxes 

There are many different kinds of taxes. They may be direct tax or indirect  tax.
 Taxes that are based on how much money a company earns are called corporate taxes 
 Taxes that are based on how much money a person earns are called income taxes. 

 Taxes that are based on how much a person buys are called sales taxes. 
 Taxes that are based on how much a person owns are called property taxes. Things like houses have a property tax on them.
 Taxes that are paid when official documents are approved are called stamp duties (because in the past the document would have a stamp put on it). Changing who owns a house will often need a document approving. 
 Taxes that are paid when somebody dies are called inheritance or estate taxes.

Taxes can also be split into 3 groups:
 Flat taxes: Everybody pays the same percentage. Russia has a flat income tax and everybody in Russia has to pay 13% of the income.
 Progressive taxes: The more money a person makes, the higher percentage of their income they have to pay. Most countries have progressive income taxes.
 Regressive taxes: The less money a person makes, the higher percentage of their income they have to pay. Sales taxes are usually called regressive as poor people spend a higher percentage of their money than rich people.

Paying lots of different taxes 
Often because different parts of governments use taxes for different things, people end up paying lots of taxes.

In the United States, for example, the national government has an income tax; most states have an income tax or a sales tax, or both; and cities and towns may have a sales tax or a property tax. In some states such as Ohio, the sales tax is different in each county.

Before Taxes 
In ancient times, people from one city or area would attack another place, and make the people there pay tribute. Tribute meant that the attacked people would pay money (or other things), and the attacker would stop attacking them. A famous tribute was the Danegeld, when people from Denmark conquered part of England and made the English pay thousands of silver coins.

Groups who are against taxes 
Anarchists and Libertarians are against all taxes or against high taxes. As people are paying them unwillingly and under the threat of sanctions, they say that taxation is the same as robbery.

References 

Basic English 850 words
An oboe is a woodwind instrument with a double reed. It looks very similar to the clarinet, and may be confused with it. While the clarinet's shape remains cylindrical, the oboe's body is conical. The sounds produced by clarinets and oboes are very different. An oboe's sound is produced by blowing air through the double reed at the upper end of the instrument which forces the two reeds to vibrate together which produces the sound. The oboe has four parts: the bell, lower joint, upper joint, and the reed. A person that plays the oboe is called an oboist. A typical orchestra may have two oboes but sometimes three. Sometimes there is also a cor anglais which sounds a fifth lower than the oboe. Very occasionally there is also a bass oboe, which sounds an octave below the oboe. Gustav Holst used one in his Suite "The Planets".

The oboe came from the shawm which was a medieval and Renaissance instrument. It became popular in the Baroque period. Bach and Handel both used it in most of their orchestral music. Many Italian composers such as Antonio Vivaldi wrote concertos for the instrument, and it is used in a lot of chamber music. At this time it hardly had any keys, but over time more keys were added which made it easier to play the sharps and flats.

Later composers to write for the oboe as a solo instrument include Mozart, Weber, Richard Strauss, Vaughan Williams and Francis Poulenc.

It is normal for the principal oboist in an orchestra to play the note A for the rest of the orchestra to tune their instruments to.

The name oboe comes from French language hautbois, meaning "high wood", a high-pitched woodwind instrument.

Double reed instruments
Eric Idle (born 29 March 1943) is an English actor, comedian, composer, musician, singer-songwriter and writer. He is one of the members of Monty Python. Monty Python is a British comedy team.

Eric Idle was born on 29 March 1943 in South Shields, County Durham, England. He studied English at Pembroke College, Cambridge.

Eric is known for his songwriting and singing skills. His songs were important parts of the Monty Python television programme and movies. He wrote the song "Always Look on the Bright Side of Life". This song was written as the closing song of the 1979 movie Life of Brian.

Eric lives in Studio City, California.

Other websites 

1943 births
Living people
Actors from County Durham
Alumni of the University of Cambridge
English comedians
English movie actors
English television actors
English voice actors
Grammy Award winners
Monty Python
Naturalized citizens of the United States
Adelaide is a city in Australia. It is the capital city of the state of South Australia, and it has an approximate population of 1.2 million people.

It is the fifth biggest city in Australia, behind Sydney, Melbourne, Brisbane and Perth. Adelaide was founded in 1836 by Colonel William Light, who named it after Queen Adelaide.

Adelaide is near the Southern Ocean and is north of the Fleurieu Peninsula. It has a river going through it called the River Torrens. Many festivals are held there. Adelaide has a hot-summer and cool-wet-winter Mediterranean climate. Grapes for wine production are grown in the Barossa Valley about 50 kilometres (30 miles) northeast of Adelaide, in the McLaren Vale about 30 kilometres south of Adelaide and parts of the Mt Lofty Ranges to the east.

References

Other websites 

 Adelaide Airport

1836 establishments
 
1830s establishments in Australia
Yoshi is a fictional dinosaur who appears in the Mario series of video games made by Nintendo. The character was created by Shigeru Miyamoto. 

Yoshi's best-known ability is his ability to eat enemies. He has a long tongue which he uses to grab enemies and eat them. In some games, after Yoshi eats enemies, they turn into eggs, which can be thrown.  One of Yoshi's best friends is Mario who helps Yoshi throughout the dangerous situations. Sometimes, Mario can ride Yoshi. 

Yoshi also can jump very high, and can also float in the air a little bit by kicking his legs. He can also ground pound enemies by quickly jumping on them.

Yoshis are usually green, but can come in many other colors. These other colors include green, red, cyan, blue, pink, yellow, brown, black, or white. Blue Yoshi is especially in Super Mario World. In Super Mario 64 DS,  Rec Room there's a light blue color in one of Yoshi's minigames Tox Box. In Vs Mode. Multiplayer, it has a dark blue color and the third player can play him.

In some games, Yoshi gains powers, like flying or shooting fireballs, by eating the shells of enemies known as Koopalings, which look like turtles.

Yoshi first appeared in the game Super Mario World (SNES), which was released in 1990 in Japan and 1991 in the United States.

Main playable appearances
Mario Kart 64 (N64)
Mario Kart: Super Circuit (GBA)
Mario Kart DS (DS)
Mario Kart Wii (Wii)
Mario Kart 7 (3DS)
Mario Party series (N64, GCN, DS, and Wii)
Super Mario 64 DS (DS) (Vs Mode multiplayer only, the one with the game card is Green Yoshi, others are Red, Blue, and Yellow Yoshi.
Super Mario Kart (SNES)
Super Mario Sunshine (GCN)
Super Smash Bros. (N64)
Super Smash Bros. Melee (GCN)
Mario Kart: Double Dash!! (GCN)
Mario Power Tennis (GCN)
Super Mario Strikers (Wii)
Super Mario World (SNES)
Yoshi's Island (SNES), (GBA)
Yoshi's Island DS (DS)
Yoshi Touch & Go (DS)
Yoshi Topsy-Turvy (GBA)
Yoshi's Story (N64)
Mario Strikers Charged Football (Wii)
Super Smash Bros. Brawl (Wii)
Super Mario Galaxy 2 (Wii)
New Super Mario Bros. U (Wii U)

Reception
Yoshi is a very well-known character in the Mario series. Yoshi is also seen a lot in Mario toys, games, and shirts. Yoshi was in two of the Mcdonald's Happy Meal Mario toy promotions, which only starred Mario, Donkey Kong and Yoshi himself. In a 2008 poll, Yoshi was voted as the third favorite video game character in Japan. Cloud Strife and Mario were second and first place, in that order.

References

Fictional animals
Fictional characters introduced in 1990
Mario series characters
Fictional dinosaurs
A lake (from Latin lacus) is a large body of water (larger and deeper than a pond) within a body of land. As a lake is separated from the ocean, it is not a sea. Some lakes are very big, and people in the past sometimes called them seas. Lakes do not flow like rivers, but many have rivers flowing into and out of them.

Most lakes on the surface of the Earth are fresh water and most are in the Northern Hemisphere. More than 60% of the lakes of the world are in Canada. Finland is known as The Land of the Thousand Lakes (there are 187,888 lakes in Finland, of which 60,000 are large).

Many lakes are man-made reservoirs built to produce electricity, for recreation, or to use the water for irrigation or industry, or in houses.

If there are not rivers flowing out of the lake (see Endorheic basin), or they are few and small, the lake loses water only by evaporation or because the water flows through the soil pores. Where the water evaporates rapidly and the soil around the lake has a high salt level, as in very dry places, the water of the lake has a high concentration of salt and the lake is called a salt lake. Examples of salt lakes are the Great Salt Lake, the Caspian Sea, the Aral Sea, and the Dead Sea.

Largest lakes by continent 

 Africa - Lake Victoria, also the second largest freshwater lake on Earth. It is one of the Great Lakes of Africa.
 Antarctica - Lake Vostok.
 Asia - Lake Baikal is the largest lake that is completely in Asia. The Caspian Sea, the largest lake on Earth, is on the Europe-Asia border (an artificial border) and so both continents share this lake.
 Australia - Lake Eyre, that most of the time is without water; it takes water when it rains a lot.
 Europe - Lake Ladoga, followed by Lake Onega, both in northwestern Russia.
 North America - Lake Superior.
 South America - Lake Maracaibo but it is like a bay because it has a wide opening to sea. The largest freshwater lake of South America is Lake Titicaca, which is also the highest body of water on Earth at 3,821 m (12,507 ft) above sea level where boats can travel.

Notable lakes 
 The largest lake in the world by area is the Caspian Sea, with 394,299 km². The largest freshwater lake by area is Lake Superior (82,414 km²), part of the Great Lakes.
 The longest freshwater lake is Lake Tanganyika, with a length of about 660 km. Lake Baikal is the second longest (about 630 km from tip to tip).
 The deepest lake is Lake Baikal in Siberia, with a bottom at 1,637 m (5,371 ft). Lake Tanganyika (1,470 m) is the second deepest lake.
 The highest lake of the world is a small lake (pond) without a name on Ojos del Salado at 6,390 m (20,965 ft). But the highest navigable lake is Lake Titicaca in Peru and Bolivia at 3,812 m (12,507 ft).
 The lowest lake of the world is the Dead Sea, bordering Israel and Jordan at 418 m (1,371 ft) below sea level. It is also one of the lakes with highest salt concentration.
 Lake Enriquillo in Dominican Republic is the only saltwater lake in the world where crocodiles live.

Related pages
 List of lakes

References 

 
Biomes
East is one of the 4 main directions on a compass (called cardinal directions). East is normally to the right on most maps. For example: Japan is east of China, which is itself east of Pakistan. When “The East” is described: it usually refers to the countries of Asia (especially from Pakistan eastwards like China and India). The sun and moon are also seen to rise in the east.

Basic English 850 words
Compass directions
A tire is a ring of material that covers the rim of a wheel. Most road vehicles and many other vehicles use rubber tires. Tires help vehicles to move smoothly. Some metro trains and trams also use rubber tires on their steel wheels to provide better traction than the steel tires of other trains.

Tires need to be changed after their treads wear away. Driving with worn tires is very dangerous. It can cause the tire to explode and the driver to lose control.

Tires were made of leather for thousands of years, and of iron or steel for hundreds. Pneumatic tires were invented in the 1840s and again in the 1880s. They became commonplace early in the 20th century.

Construction
Tires are made of different types of rubber. Softer rubber is used in summer or when the tires need better traction, for example, in auto racing. Tires made of harder rubber are made for long lasting performance, like long-distance truck carriers. There are many different types of tires. They come in different sizes and have different tread patterns.  

There are many different sizes of tires. On car and truck tires, they are marked with 3 numbers and might look like: 225/60R16.  The first number is the width in millimeters of the tire at the widest point when it is mounted and inflated. The second number is the sidewall (side of the tire) height as a ratio or percentage of the width. The last number is the wheel diameter in inches.

Example
Tire size: 225/60R16
Tire width = 225mm
Sidewall height = 135mm (225 * .60 = 135)
Wheel diameter = 16 inches

Very large tires (for example, tires on big mining trucks) use different units. For example: 59/80R63. The first number is the width in inches of the tire. The second number is the sidewall height as a ratio of the width. The last number is the wheel diameter in inches.

Tire damage
Most tires today do not have a tube inside of them. There are grooves in the wheel that let the tire be popped into place and hold a lot of air pressure. If there is a crack in the tire, it will not be able to hold its air. Tire leaks are very common. The most common cause is a hole from a nail or screw. This can usually be fixed by patching the inside of the tire so that it can hold air again. If the hole is close to or in the side of the tire, it can not be fixed. This is because the sides of the tire flexes to support the weight of the vehicle. A patch will not be able to handle the stress.

Mud and snow tires 
Mud and Snow, (or M+S, or M&S), is a designation used by manufacturers for all-season and winter tires. Most are designed to provide improved performance under low temperature conditions, compared to summer tires. The tread compound is usually softer than that used in tires for summer conditions. This provides better grip on ice and snow, but wears more quickly at higher temperatures. Tires may have well above average numbers of sipes in the tread pattern to grip the ice. M&S relates to the percentage of tread void area. On four-wheel drive vehicles, M&S tires are often standard equipment.

References 

Auto parts
Polymers
A population is the number of living people that live together in the same place. A city's population is the number of people living in that city. These people are called inhabitants or residents.  The population includes all individuals that live in that certain area.The world population was estimated to have reached 7.5 billion in April 2017.  Asia is the most populous continent, with its 4.3 billion inhabitants being 60% of the world population.  The most populous country is China with 1.4 billion people.

Population density is the average number of people in a place. Urban areas such as big cities have a high population density. People there live close to each other. In areas with a low population density, people usually live far away from each other, such as in rural areas out in the countryside.

Usually population refers to the number of humans in a certain area. The maximum population that can be supported in an area is called the carrying capacity.

Population trends 
Global population is going up, but the population growth rate is declining all over the world.  Growth in poor countries is faster than in rich ones; some rich countries have a population pyramid that is nearly square. Urbanization is also common, and urban areas usually have lower birth rates. In population growth, births exceed deaths. In the modern world this is due to reduction of infant deaths, control of infectious diseases, and improved agriculture so more people can eat.

The change in population from 2010 to 2015 was:
 World: +420 million
 Africa: +146 million
 Asia: +223 million
 Europe: +3 million
 Latin America and Caribbean: +35 million
 Northern America: +14 million
 Oceania: +2.9 million

Human population control is the practice of altering the rate of growth of a human population. Concerns about overpopulation and its effects on poverty, environmental degradation, and political stability led to efforts to reduce population growth rates.

Related pages 
 Population growth
 Overpopulation
 Census

References

Further reading 

 YAN Kun(2011). The tendency equation of the population and its limit value in the United Kingdom (Brief annotation of the connection equation(R)), Xi'an: Xi'an Modern Nonlinear Science Applying Institute.

Social sciences
Snow is a form of ice. Snow forms when water in the atmosphere becomes frozen. Snow comes in all different shapes and sizes.

At the freezing point of water (0° Celsius, 32° Fahrenheit), snow melts and becomes liquid water. Sometimes, the snow will melt very fast and become water vapor. This is called sublimation. The opposite, where water vapor becomes snow, is called deposition.

Snow is used for some winter sport activities like skiing and sledding. Sometimes people make artificial snow so they can ski. People also commonly build things out of snow for fun.

Snow can also be dangerous, as it can lower visibility and make driving very difficult. When it snows, the snow will melt a little during the daytime and freeze again at night. This makes ice which can make driving conditions very treacherous. Snow plows are used to remove snow from roads to make driving easier and safer. Also, sand or salt may be added to the road to help tires grip the road. When salt is mixed with snow, the snow will melt more easily. This is because salt water has a lower melting point than fresh water (water without salt).

A blizzard is a dangerous type of a snowstorm. A blizzard produces strong winds that keep the snow in the air, thus reducing visibility. Sometimes it produce thunder snow, which is snow with lightning and thunder.

References

Snow
Snow
A
Air resistance

C
Compression --Critical angle -- Colour filter -- Concave lens -- Convex lens

D
Diffraction -- Density (distance)--(displacement)

E
Electromagnetic spectrum -- Energy --

F
Fluid friction -- Focus -- Force sensor -- Frequency -- Friction --
Flotation

G
Gamma ray -- Gravity

I
Inertia -- Interference

K
Kinetic energy

L
Lamp-housing -- Laser pointer -- Lens -- Longitudinal wave -- Longitudinal wave model (Crova's disc) --

M
Moment of inertia

N
Normal -- Normal force -- Newton's laws of motion

O
Oscilloscope - Overhead projector

P
Plane mirror -- Potential energy -- Prism

R
Rarefaction -- Ray box -- Reflection -- Refraction -- Ripple tank  --
relative density refleaction of light through prism

S
Signal generator -- Slinky -- Slit plate -- Spring -- String theory -- Sound -- Statistical mechanics

T
Tension -- Translucent screen -- Transverse wave -- Transverse wave model --

V
Vibration -- Velocity

W
wave -- Wave speed -- Waveform -- Wavefront -- Wavelength --

Y
Young's double-slit experiment

Science-related lists
A president is the leader of a country or a company or other group. A president is usually elected by the people in that group. Voting is one way to elect a president.

Electing a President 
The President of the United States is elected by the electoral college. Some other countries choose a president this way. In some, the Parliament does it. Some countries have direct elections to choose a president. Many countries have a monarch instead of a president and some have neither.

Companies have presidents. They are elected by the people who own part of the company. In some companies, the people who are workers for the company elect (vote for) their company president.

Power of a President 
The president of a country is not the same thing as a prime minister. A prime minister is part of a parliament, but a president is not. In some countries, (such as the United States or France), the president has more power and responsibility than anyone else.  Such a president is often called the nation's chief executive.  As chief executive, the president must take an active role in all phases of government.  In other countries (such as India, Israel or the Republic of Ireland), to be president is more of an honor or a symbol, and the position has no real power.  This kind of president is often called "head of state". 

Most countries that have a King or Queen as their monarch have no president. 

The American President is restricted by the written United States Constitution, which was written to make sure that the American executive never became as powerful as in the British system.  The British Prime Minister is part of both the Legislature and Executive, whereas the American President is the head of the Executive. The American governmental system shows a clear separation of powers unlike the British system.
         
 All the president's ministerial appointments have to be vetted by Congress (Parliament) and Congress may have an opposition majority.
 The president does not have the ability to introduce and influence legislation in the same way as the British prime minister.
 Congress has much greater control over the budget and foreign policy than the British Parliament.
 There are broad areas of American life, such as education, crime and punishment, over which the president has virtually no influence at all.
 The president even has very limited control over the economy.

So despite having a large nuclear arsenal, the American president can not carry out policy and introduce legislation as freely as the British prime minister.

Related pages
 Head of state
 Monarch

Other websites 
 Presidents of the United States

 
Titles
When a person agrees to do something or to not do something, that person is making a promise. A promise can be made   (by saying it), or it can be written down as a contract. Breaking a promise, or not keeping it, is often just bad manners, but it can sometimes be illegal, such as when a contract is not kept.

A vow is a special promise.  It is mostly used in a religious sense or in ceremonies such as marriages when the couple who are being married make their "marriage vows", promising to be faithful to one another.

An oath is a promise in the legal sense.  When someone has to give evidence in a court of law they "swear an oath".  This means that they promise they will tell the truth.

Ethics
Law
The water cycle (or hydrological cycle) is the cycle that water goes through on Earth.

Water is essential for life as we know it. It is present throughout the Solar System, and was part of the Earth from its formation. The source of the water was the same as the source of the Earth's rock : the cloud particles which condensed in the origin of the solar system.

Processes
This is the process that water starts and ends in the water cycle.
 The cycle starts when water on the surface of the Earth evaporates. Evaporation means the sun heats the water which turns into a gas.
 Then, water collects as water vapour in the sky.  This makes clouds.
 Next, the water in the clouds gets cold. This makes it become liquid again. This process is called condensation.
 Then, the water falls from the sky as rain, snow, sleet or hail. This is called precipitation.
 The water sinks into the surface and also collects into lakes, oceans, or aquifers. It evaporates again and continues the cycle.

Humans activities that affect the water cycle
Human activities that change the water cycle include:
 Agriculture
 Industry
 Building dams
 Deforestation
 Removing groundwater from wells
 Water abstraction from rivers

Related pages 
 Carbon cycle
 Rock cycle
 Drought
 Ecohydrology
 Flood
 Rain
 Bioprecipitation

References 

cycle
Weather
Earth sciences
Evaporation is when a liquid becomes a gas without forming bubbles inside the liquid volume. If bubbles are formed we are talking instead about "boiling".

For example, water left in a bowl will slowly disappear. The water evaporates into water vapor, the gas phase of water. The water vapor mixes with the air.

The opposite of evaporation is condensation.

When the molecules in a liquid are heated, they move faster. This makes them full of energy and so the particles collide with each other, and eventually they become so far apart that they become a gas.

Differences between evaporation and boiling 
During evaporation only the molecules near the liquid surface are changing from liquid to vapor. During boiling the molecules inside the volume of the liquid are also changing to vapor. For this reason during evaporation no bubbles are formed, instead they are formed during boiling.

Evaporation can happen at any temperature, while boiling happens only at a specified temperature called the "boiling point". Evaporation happens slowly, but boiling happens quickly.

Rate of evaporation 
Some liquids evaporate more quickly than others. There are many factors that affect the evaporation rate.

The rate of evaporation depends on the liquid's exposed surface area (faster when increased), the humidity of surroundings (slower when increased), the presence of wind (faster when increased) and the temperature (faster when increased).

Liquid with high boiling points (those that boil at very high temperatures) tend to evaporate more slowly than those with lower boiling temperatures.

Evaporation is a very essential part of the water cycle.

Related pages
 Boiling

References

Materials science
Gases
A contract is an agreement or promise that the law can enforce. The law will enforce some agreements but not others. For example, in most places, if a parent promises to take a child to get ice cream, the law will not enforce that promise as a legal contract.

The legal rules about which promises are enforced by the law can be different in different places (or jurisdictions), but a contract is usually enforced only if it is made by people or groups who want it to be enforced and who know what they are doing.

Sometimes, a contract is written down and signed by the people agreeing to it, but it does not always need to be. People usually sign a contract when something important or costly is being done. For example, when people take a job, they will sometimes sign a contract with their employers. The contract will show what the person must do as part of his job, how much they will be paid, and so on. The person and the employer will sign the contract, and it will become a legal promise.

If someone breaks a contract, another person might sue him or her. In a lawsuit about a contract, the court will look at the contract, listen to what the people who made the contract say about it, and then make a decision about what the contract means.

Related pages
 Law 
 Oath

Law
Documents
Kolkata (spelled Calcutta before 1 January 2001) is the capital city of the Indian state of West Bengal. It is the second largest city in India after Mumbai. It is on the east bank of the River Hooghly. When it is called Calcutta, it includes the suburbs. This makes it the third largest city of India. This also makes it the world's 8th largest metropolitan area as defined by the United Nations. Kolkata served as the capital of India during the British Raj until 1911. Kolkata was once the center of industry and education. However, it has witnessed political violence and economic problems since 1954. Since 2000, Kolkata has grown due to economic growth. Like other metropolitan cities in India, Kolkata struggles with poverty, pollution and traffic congestion.

History 

The discovery of the nearby Chandraketugarh, an archaeological site has proved that people have lived there for over two millennia. The history of Kolkata begins when the English East India Company arrived in 1690. Job Charnock, an administrator with the Company is traditionally known as the founder of this city. However some academics say that Charnock is not the city's founder.

At that time Kolkata, ruled by the Nawab of Bengal Siraj-Ud-Daulah, had three villages. They were Kalikata, Govindapur and Sutanuti. The British in the late 17th century wanted to build a fort near Govindapur. This was to become more powerful than Dutch, the Portuguese, and the French. In 1702, the British completed the construction of old Fort William, which was used to station its troops and as a regional base. Calcutta was declared a Presidency City, and later became the headquarters of the Bengal Presidency. When regular fights with French forces started, in 1756 the British began to upgrade their fortifications. When this was protested, the Nawab of Bengal Siraj-Ud-Daulah attacked and captured Fort William. This led to the infamous Black Hole incident. A force of Company sepoys and British troops led by Robert Clive recaptured the city the next year. Calcutta became the capital of British India in 1772,. However, the capital shifted to the hilly town of Shimla during the summer months every year, starting from the year 1864.  Richard Wellesley, the Governor General between 1797–1805, helped in the growth of the city and its public architecture. This led to the description of Calcutta as "The City of Palaces". The city was a centre of the British East India Company's opium trade during the 18th and 19th century; locally produced opium was sold at auction in Kolkata, to be shipped to China.

References

Other websites

Former national capitals
Resurrection means bringing someone back to life after they have died.

Polytheistic religions
The idea of resurrection is found in writings of ancient polytheistic religions in the Middle East. Some Egyptian and Canaanite writings tell of gods being resurrected, such as Osiris and Baal.

In Greek mythology, many men and women were given eternal life by being resurrected from the dead. In their stories, some who came back to life as gods were Alcmene, Castor, Heracles, and Melicertes. But the Greek philosophers at that time did not believe in a physical rebirth.

Abrahamic religions

Christianity 

Christians believe that Jesus Christ was resurrected. They also believe in resurrection for all people after they die. This is based on the Gospels and on Saint Paul's writings in the New Testament.  The resurrection of Jesus is the Christian belief that he returned to life by a miracle. He died by crucifixion on Friday and rose from his tomb to new life on Sunday morning. This belief is celebrated at Easter.

The resurrection of Jesus Christ is written about by the evangelists in the New Testament. They are the authors of the four Gospels in the New Testament.  Christians believe the resurrection is a central part of the Christian faith. Jesus died on the cross to save mankind.  When he was resurrected, Jesus defeated death.  He is alive forever and sitting at God's right hand on a throne. This gives Christians the hope of a new life after death. This is because his resurrection mirrors the future for all Christians after they die.

With Jesus Christ and with humans, the Bible shows that the resurrected body is changed from the original.  This is because the human body, while alive, is weak and frail.  But, the resurrected person lives for ever.

All four Gospels tell about Jesus being raised from the dead. They also write about three times that Jesus brings a dead person back to life:
 Daughter of Jairus. Jairus, a patron of a synagogue, asks Jesus to heal his daughter, but while Jesus is on the way, Jairus is told his daughter was dead. Jesus tells him she was only sleeping, and wakes her with the words Talitha kum.
 The Young Man from Nain. A young man, the son of a widow, was on the way to be buried in Nain. Jesus sees the widow crying and so he tells her not to cry. Jesus tells the dead man inside to get up, and he does so.
 The Raising of Lazarus. A close friend of Jesus who had been dead for four days is brought back to life. Jesus goes to his grave and commands him to get up.

Islam 
In Islam, the Quran refers to a bodily resurrection of all those who have died.
This will be followed by a final time of trouble and eternal division of the righteous and wicked. Islamic apocalyptic literature describing Armageddon is often known as The Great Massacre or ghaybah in Shī'a Islam. The righteous are rewarded with the pleasures of Jannah (Paradise), while the unrighteous are punished in Hell.

Science 
According to Alcor, resurrection of legally dead people will be possible in the far future. They are using cryonics to preserve some legally dead people until the invention of the resurrection.

References 

Theology
Afterlife