cahya/simple-wikipedia huggingface dataset:
A parliament is a type of legislature. 

The most famous parliament is probably the Parliament of the United Kingdom, which is sometimes called the "Mother of all Parliaments".  The word "parliament" comes from the French word parler, which means a talk. 

The Althing, the national parliament of Iceland, was founded earlier (930 AD), so it is the oldest legislature in the world still existing. However, the Althing did not function as a legislature for four centuries, and its role as a primary legislature is modern.

Other parliaments 
Other parliaments have copied the UK and work similarly. They have three levels - a lower house which makes the law, an upper house which reviews the law (Decides if they like it or not, and suggest changes to it), and a head of state who is mostly for show and who starts and ends each year of parliament. The Prime Minister is almost always the person whose party has the most seats, but if the lower house does not think he is doing a good job they can call a vote of no confidence and ask him to leave his job as Prime Minister or have an election.

The word "parliament" 

Sometimes people use the word "parliament" to describe a legislature, even if it is not a real parliament. A "parliament" is a type of legislature which has a Prime Minister.

Similar to a congress 

A parliament is a lot like a congress but a congress cannot ask the head of the government to leave his job. Also, a congress runs for a number of years according to the country's constitution, but a parliament can be stopped as long as enough members agree. Elections are held after this happens.

Countries that have Parliaments 

 Australia
 Belgium
 Canada
 Ghana
 Germany
 Greece
 Iceland
 India
 Israel
 Italy
 Malaysia
 Moldova
 Netherlands
 New Zealand
 Pakistan
 Romania
 Russia
 Ukraine
 United Kingdom
 Bulgaria

Related pages
Constitution
Constitutional economics
Democracy
Legal rights

References
A fuel is a substance that is changed in some way to produce heat, electricity, or other forms of energy. This is usually by being burnt, although there are exceptions, such as nuclear fuel. Fuel can be divided into two main types: fossil fuels and other fuels.

Fossil fuel 

There are several kinds of fossil fuels:
 coal
 oil and products that are refined from oil (gasoline, diesel, kerosene)
 natural gas
Some people do not want us to use fossil fuels because they may pollute the environment. Because all fossil fuels are made out of carbon, burning them makes carbon dioxide. Some people think that too much carbon dioxide in the air may cause a greenhouse effect. Fossil fuels are also non-renewable, or renew extremely slowly (thousands of years). This means that we will eventually run out of fossil fuels.

Other fuels 
Other fuels are not made from fossils. Some of these, like nuclear and hydrogen, do not have carbon in them. Others, like wood or ethanol, do have carbon in them. Some examples of these fuels are:
 Nuclear fuel (uranium, plutonium, thorium, etc.)
 Hydrogen
 Extracted from the wind
 Biofuels from biomass
 Firewood
 Biodiesel (a diesel-type fuel made from plants)
 Ethanol (made from grains or other plants)
These fuels are renewable. This means that we can make more of them if we run out. For instance, if we run out of ethanol, we can grow some more corn and make some more ethanol.

Other websites

Fuel
Latvia is a country in Northern Europe. The capital is Riga. It is one of the Baltic States, together with Estonia in the north and Lithuania in the south. Latvia's neighbours to the east are the countries Russia and Belarus. Latvia is split into four parts called Kurzeme, Vidzeme, Zemgale, and Latgale.

People from Latvia are called Latvians. They speak the Latvian language, which is a little like the Lithuanian language, though not close enough to be understood.

History 
Latvia was settled by the Baltic tribes thousands of years ago. They mainly fished, hunted, and traded.

German traders and crusaders came to Latvia at the end of the 12th century. Latvians lost control of their homeland. Over the next 800 years, Germans, Danes, Swedes, Poles, and Russians all invaded Latvia. Latvia finally became independent in 1918.

During the all time before the World War I the aristocracy were mainly  German.

During the Great Northern war (1700-1721) modern-day Latvia became the part of the Russian empire. There were organized Courland and Livonia governorates.

In 1940 Latvia became Soviet republic and joined to the Soviet Union.
It was under Nazi occupation during the World War II in 1941-1944. 

After the war a lot of factories were opened. Latvia became one of the successful Soviet republics.

In 1991 the Soviet Union was destroyed and new Latvian republic was declared.

Politics  
In Copenhagen on 13 December 2002, Latvia and nine other countries were invited to join the European Union. On 20 September 2003, Latvians held an election to vote on joining. Two thirds of Latvians voted to join, and on 1 May 2004 Latvia became a member of the EU.

Latvia has been a NATO member since 29 March, 2004.

International rankings

Related pages
 Latvia at the Olympics
 Latvia national football team
 List of rivers of Latvia

References

Other websites 

 Latvian Government official site

 
European Union member states
1991 establishments in Europe
Malta is a country in the European Union and considered part of Southern Europe. It is an island near the center of the Mediterranean Sea, south of Sicily. The capital of Malta is Valletta. Around 500,000 people live in Malta and it is one of the most densely populated countries in the world. Malta is 316 sq km, which makes it one of the smallest countries. Its many cities and towns grew close to each other over time.

Language 
Maltese is the national language of Malta and is influenced by Greek due to Magna Grecia settlements in Sicily.  Maltese and English are the official languages in line with the constitution of the country. A majority of the people of Malta can speak three languages; Maltese, English and Italian.

Money 
Malta had its own currency, called the Maltese Lira until 2008. The Maltese Lira was better known as the Maltese Pound because of the strong links to the United Kingdom. One Maltese Lira consisted of 100 cents. In 2008 Malta joined the Euro countries in adopting the Euro as the National Currency.

History 
People have lived in Malta since at least 5200 BC. The island has some key archaeological sites dating from early times.

Malta became well known as the base of the Knights Hospitaller. They moved to Malta after being forced to leave Palestine and then Rhodes, in Greece. In 1565 they survived a great attack by the Ottoman Empire. The history of the knights at Malta continued the strong Roman Catholic beliefs in the country that were started by the Norman and Spanish rulers.

In 1798, Napoleon took control of Malta. The French rule was not popular and in 1800 Maltese rebels invited the British Royal Navy to come to the island. This led to 200 years as a British colony and independent Commonwealth member.

During World War II, Malta was attacked this time by the Axis forces. The entire island was symbolically given the George Cross for heroism.

Malta became independent in 1964 and a republic in 1974. In 2004 Malta joined the European Union and in 2008 Malta joined the Euro.

Notes

Other websites 
 Maltese Relocation and Travel Guide
 Malta travel guide and information 
 Malta Wiki - Malta Popular Encyclopedia 
 Malta holidays and hotels
 Malta travel guide
 Malta
 Malta Travel Guide 

 
Italian-speaking countries
European Union member states
Phoenician colonies
1974 establishments in Europe
In normal cosmology, 'comoving' distance or 'proper distance' is one of several distances measured by cosmologists to define distances between objects.

Method 
To talk about the shape of the Universe, scientists want to forget that the Universe is expanding. So they separate the shape from time and pretend that the Universe is not expanding. They remember that, really, the Universe is expanding, but they write this in a variable called the scale factor. Then, the distances they talk about, while putting the scale factor to the side, are called comoving distances. When they think about the Universe using comoving distance, they think of the Universe as not expanding. This way, some calculations are easier.

Purpose 
When the part of the Universe which we can see today started, it was very small. Everything in this part of the Universe was much closer together than today. It was also very hot and photons (particles of light) were moving in different directions. Light moves very fast, but the light speed is limited and the Universe was expanding very fast.

Comparison 
Think of two ants on the surface of an expanding balloon. One ant starts moving towards another, but the balloon itself is also expanding. After a long time the balloon starts expanding more slowly. Eventually one ant reaches another. That's like photons in our universe. Some of the light from the stars you see at night traveled for billions of years to reach your eye. Surprisingly, it started very close to where you were (or the atoms of which your body consists), but just could not keep up with the universe expansion. Of course, if something else started out very close to where you were, but was not traveling toward you, it would be very far away from you now because of the expansion. 

Cosmology
Shaanxi (Chinese:陕西, also sometimes called Shenshi) is a province in east China. The word "Shaan" (viz Shanzhou) is a place in Henan Province. "Xi" means "west". So "Shaanxi" means "the place to the west of Shaan". 

Although in pinyin, "Shaanxi" is spelled exactly the same as "Shanxi", the only difference in how the two words are pronounced is that the first syllable in "Shanxi" is said using the first tone in Mandarin, while the first syllable in "Shaanxi" is said with the third tone. Since tone markers are not usually used to show how to pronounce the two different names, the first word in "Shaanxi" is spelled using the Gwoyeu Romatzyh method instead, which indicates tones by adding extra letters to a syllable.

The river Wei He runs across it. It has a large population of more than 30 million people. The capital of Shaanxi is Xi'an. It abbreviates as Shan (陕) or Qin (秦), also known as SanQin (三秦, meaning Three Qins).

History 
January 23, 1556 – A massive earthquake, measuring 9.0 on the Richter scale, strikes Shaanxi, killing over 850,000 people. This is the most devastating earthquake in recorded history.

Political divisions 

Shaanxi Province is divided into ten municipalities:

 Xi'an Municipality(西安市)
 Ankang Municipality(安康市)
 Baoji Municipality(宝鸡市)
 Hanzhong Municipality(汉中市)
 Shangluo Municipality(商洛市)
 Tongchuan Municipality(铜川市)
 Weinan Municipality(渭南市)
 Xianyang Municipality(咸阳市)
 Yan'an Municipality(延安市)
 Yulin Municipality(榆林市)

 
Provinces of China
Lisbon is the capital city of Portugal. It is the largest city of Portugal. The city has a population of about half million people. In Lisbon's urban area live around 2.8 million people, being the 10th-most populous urban area in the European Union. 
Lisbon is placed on the right bank (western) of the Tagus River, near the outfall. It has a pleasant climate and has about 220 days of sunshine each year. There are many beautiful beaches close to the city. There are also many seafood restaurants, historical sites and monuments. Lisbon is one of the oldest cities in the world.

References

Other websites 
 Official page of the city 
 Lisbon Photos a collection of Photos, showing Lisbon as it is to visitors.
 Lisbon Tourist Guide and Information

Phoenician colonies
 
719 establishments
Establishments in Portugal
Surfing is a water sport done in the ocean or sea. The surfer uses their surfboard to catch a wave and ride in towards the shore.

Surfing was invented by the Polynesians at least 4000 years ago. It has become a popular sport among both men and women of all ages. With lifestyles and regimens freer than those of most sports, surfers comprise a unique culture. Though surfing is practiced in many other Pacific nations, its center remains Hawaii, where many rounds of the international surfing championships (the ASP) are held annually. Surfing is popular in Australia, the US, and Northern Europe.

Related pages

Skimboarding
Windsurfing
Lyon (Arpitan: Liyon) is a city in the southeast of France. It is the third-largest city in the country (behind Paris and Marseille), with about 513,000 people living there in 2015. It is the second largest metropolis, or metro area, in France (behind only that of Paris), with about 2.3 million people in 2014. 

In ancient history, the name of Lyon was Lugdunum. Someone who lives in Lyon is called a Lyonnais (male) or a Lyonnaise (female) in French.

Lyon has a humid subtropical climate (Cfa in the Koeppen climate classification). It is between the Rhône and the Saône. It is about  west of the Italian border. 

The central part of Lyon, located on the peninsula between the Rhône and the Saône, was named a World Heritage Site by UNESCO.

Famous people from Lyon 
 The Lumière Brothers who created cinema
 Paul Bocuse, a world renowned chef

Sports 
Famous sports clubs from Lyon are:

 Olympique Lyonnais: The local football team that plays in Ligue 1
 ASVEL: The local basketball team
 LOU: (Lyon Olympique Universitaire) The local rugby team

Education 
 École Centrale de Lyon
 École pour l'informatique et les nouvelles technologies
 École pour l'informatique et les techniques avancées
 École spéciale de mécanique et électricité
 EMLYON Business School
 E-Artsup
 Institut Polytechnique des Sciences Avancées
 Institut supérieur européen de gestion group
 Institut supérieur européen de formation par l'action
 Sup'Biotech
 Web@cademie

References

Departmental capitals in France
 
Regional capitals in France
World Heritage Sites in France
Organic compounds are carbon-based compounds. Organic compounds contain carbon bonds in which at least one carbon atom is covalently linked to an atom of another type (usually hydrogen, oxygen or nitrogen). Most polymers are organic compounds.

History 
The name "organic" is a historical name from the 19th century.

People believed that only living things could make organic compounds and "dead" things (such as minerals) could make inorganic compounds. However, Friedrich Wöhler proved this wrong by synthesizing urea, a well-known organic compound.

Kinds of organic compounds 
There are natural organic compounds, and synthetic ones. Their structure may be described by using names, and making diagrams. 

One way of showing the molecule is by drawing its structural formula. Because molecules can have complicated structures, people have made ways to show them in simple language. One way is to use line diagrams. Each atom is shown by a letter, and connected by a line to each atom with which it is has a covalent bond. One line means a single bond, two lines means a double bond and so on. 

Because there is in an infinite number of possible organic compounds, language is needed to give a unique name to each one. The International Union of Pure and Applied Chemistry, or IUPAC, made a system for doing this. Although an IUPAC name makes every single possible molecule unique, the names are often long and complicated, so in everyday life, trivial names--unofficial but widely understood names--are used, such as the trivial names Paracetamol, Tylenol, and Acetaminophen, which are used for a compound whose IUPAC name is N-(4-hydroxyphenyl) acetamide. Some of these trivial names are trademarks.

Natural Compounds 
Natural compounds are compounds made by living beings. These could also be made in a lab, but many of these compounds are taken from nature because it is easier and less expensive to do it that way. For example, every year people grow and eat huge amounts of natural sugar and starch. Other common natural compounds are: amino acids, proteins, carbohydrates, many antibiotics like Penicillin and Amoxicillin.

Synthetic compounds 
Synthetic compounds are those made by people. Sometimes, this is done by taking something natural and changing the molecule in a small way, such as making glycerin from vegetable oils. Other compounds are synthesized in long, complicated reactions with many steps. Plastics are sometimes mostly natural, and other kinds are manufactured.

Structure 
Since a compound is often first discovered in nature instead of being made on purpose in a lab, people may know the compound exists, and even know what it does sometimes, but not know exactly what atoms it is made of and how it is arranged. There are several ways of taking an unknown compound and finding out this structure:
 Mass spectrometry
 X-ray diffraction
 Nuclear magnetic resonance spectroscopy
 Infrared spectroscopy

Related pages 
Acetone
Inorganic compound
Organic chemistry
Biochemistry

Other websites 
 Organic chemistry online
Natural gas is a mixture of gases. It consists mainly of hydrocarbons. The main component is methane. Natural gas is often found in the ground, either alone or together with petroleum. Landfills and natural processes produce a little methane. Usually it is transported to users in a pipeline.

Most natural gas is burnt as a fuel to produce energy. It burns with a clean blue flame, causing little pollution.

Natural gas is burned to produce electricity, to cook and to heat buildings. It is also used as fuel for natural gas vehicles for transport. When natural gas is burned in a power station it boils water into steam that spins a steam turbine that turns a generator to make electricity. Some power stations use natural gas in a gas turbine. 

Natural gas is also converted into many different industrial chemicals. It is the most common feedstock for making pure hydrogen. Hydrogen is used as fuel in fuel cells, and to make ammonia. Ammonia is used as a fuel, as a fertilizer for crops, and for making many other things. Natural gas is also converted into monomers to make many plastic products.

Related pages

Fossil fuel
Coal
non-renewable resource

Other websites 
History of using natural gas from the U.S. Department of Energy

References 

Fossil fuels
Hydrocarbons
Jewels (or gems or gemstones) are rare minerals. They usually come in colours and sizes. They begin in a rough rock form, but can be cut and polished to turn into a jewellery.

However, some other non-mineral rocks (such as lapis lazuli) or organic materials can also be also used for jewelry and are called gemstones. These include amber or jet. Pearls and coral are sometimes also called gemstones.

Most gemstones are hard. Soft minerals are used in jewelry too, because of their luster that gives them value. 

Being rare or in short supply also makes a gemstone valuable.

History 
The Ancient Greeks began to decide which gems are precious and semi-precious. This continued in other cultures. 

In modern times, the precious stones are diamond, ruby, sapphire and emerald, with all other gemstones being semi-precious.

Types 
 Amethyst
 Aquamarine
 Diamond
 Emerald
 Jade
 Peridot
 Ruby
 Sapphire
 Topaz
 Turquoise
 Opal
 Spinel

References

Other websites
 "Book of Royal Gemstones" is a book from 1554 that talks about gemstones.
 "The Blossoms of Thoughts Regarding the Precious Stones" is an old book from the 1600s that is considered one of the most important books about precious stones. It is written in the Arabic language.

Basic English 850 words
Xenon is a non-metal chemical element. It has the chemical symbol Xe and atomic number 54. It is one of the few elements that are a gas at the standard temperature and pressure.

History 
Sir William Ramsay and M. W. Travers discovered this element in 1898. The element's name came from the Greek word xenos, which means 'stranger'.

Chemistry 
Xenon belongs to the group of the noble gases. Noble gases are very unreactive. However, in 1962, chemists have found that xenon can react with fluorine under special conditions, such as high pressure and high temperature. It is not known why xenon behaves differently under these circumstances. There are also some compounds with oxygen. The gas is not very reactive, because if fulfills the octet rule. This means that a lot of energy is needed to remove an electron from xenon. This activation energy for xenon is 1172 kJ/mol. To remove a second electron from xenon, an energy of 2046.4 kJ/mol is needed.

Known oxidation states of xenon are 0, +1, +2, +4, +6 and +8. However, the most stable form is pure xenon, or the xenon's oxidation state of 0. Xenon has 8 stable isotopes and more than 30 unstable isotopes.

Uses 
Xenon gas is used in electron tubes, bactericidal lamps, trobe lamps, and lamps used to excite ruby lasers.
It has the atomic mass of 131.294 and is the 5th inert gas in the inner gas group.

Xenon is also a trace gas in the atmosphere, occurring at 87 ±1 nL/L (parts per billion) or approximately 1 in 11.5 million. It is also emitted from some mineral springs.

Related pages
 Periodic table
 List of common elements

Noble gases
Brass is an alloy of copper and zinc. Some types of brass are called bronzes.

Brass has a golden appearance. It is harder than pure metals and resists corrosion. It costs more than zinc.

There are some common brasses:
 Alpha brasses - with less than 40% zinc
 Beta brasses - 
 White brasses - with more than 45% zinc

Things brass are used to make include:
 Brass instruments
 Ornaments
 Electrical fittings
 Buttons
 Screws
 Taps
 Hinges
 Door knobs

Properties
Brass is more malleable than bronze or zinc. The melting point of brass can be 900 to 940 °C or 1,650 to 1,720 °F, depending on what it is made of. The density of brass is 8.4 to 8.73 g/cm3 (0.303 to 0.315 lb/cu in). 

Today, almost 90% of all brass alloys are recycled. Brass is not ferromagnetic. Brass scrap is collected and transported to the foundry. In the foundry, it is melted and recast into billets. The billets are heated and stretched into the form and size that is wanted.

Brass will corrode when it is exposed to moisture, chlorides, acetates, ammonia, and some acids.

Brass alloys 
There are many brass alloys. They include:

 Abyssinian gold
 Admiralty brass
 Aich's alloy
 Aluminum brass
 Arsenical brass
 Cartridge brass
 Common brass
 DZR brass
 Delta metal
 Free machining brass
 Gilding metal
 High brass
 Leaded brass
 Lead-free brass
 Low brass
 Manganese brass
 Muntz metal
 Naval brass
 Nickel brass
 Nordic gold
 Orichalcum
 Prince's metal
 Red brass
 Tombac
 Silicon tombac
 Tonval brass
 Yellow brass

References 

Alloys
Basic English 850 words
A body is the physical material of a person or organism. It is only used for organisms which are in one part or whole. There are organisms which change from single cells to whole organisms: for example, slime moulds. For them the term 'body' would mean the multicellular stage. Other uses:
Plant body
Cell body: here it may be used for cells like neurons which have long axons (nerve fibres). The cell body is the part with the nucleus in it.

The body of a dead person is also called a corpse or cadaver. The dead bodies of vertebrate animals and insects are sometimes called carcasses.

The human body has a head, neck, torso, two arms, two legs and the genitals of the groin, which differ between males and females.

The study of the body is anatomy.                                                                                                                                                                                            

The study of the workings of the body is physiology.

Here are the names of the body parts of a woman and a man. 

The word body is sometimes used in other ways.  For example, a lake is a body of water. The laws on a topic are a "body of law".

Related pages 
 Human body

Body parts
Basic English 850 words
An alloy is a uniform mixture. It is made up of two or more chemical elements, of which at least one is a metal. An alloy has properties different from the metals it is made of.

Most alloys are made by melting the metals, mixing them while they are liquid to form a solution, then leaving them to cool and turn solid again.

Theory 
Combining a pure metal with one or more other metals or non-metals often makes it better. For example, steel is an alloy made from iron but it is stronger than iron. Physical properties like density, reactivity and electrical and thermal (heat) conductivity may not be much different than the elements (substances) which make the alloy. But, properties like strength can be very much different.

The first alloy to be discovered was Bronze. Bronze is made from copper and tin. Bronze was discovered a very long time ago in  the prehistoric period. Then, bronze was being used for making tools and weapons. This period was known as Bronze Age. But, later better alloys were discovered which replaced bronze for making tools and weapons. Now, bronze is used for making ornaments, statues, and bells. Brass is another alloy made from copper and zinc.

Melting point is the temperature at which a solid changes to liquid. Most alloys do not have a single melting point. They have a melting range in which the alloy is a mixture of solid and liquid stages. The temperature at which melting just starts is called solidus and the temperature at which the melting is just finished is called liquidus.

Terms related to alloys 
The term alloy means a mixture of atoms in which the main substance or the primary constituent is a metal. This primary metal is called the base or matrix.

If an alloy has only two types of atoms, like copper-nickel alloy, then such an alloy is called binary alloy. If an alloy has three types of atoms, like iron, nickel and chromium, then it is called a ternary alloy. An alloy with four types of atoms is called a quaternary alloy and an alloy with five types of atoms is called a quinary alloy.

Different varieties or forms of alloys can be made from the same constituent materials (substances from which the alloy is formed). These different forms or varieties can be formed by using different amounts of the constituents.

Some common alloys 
There are some common alloys:

 Brass is made of 35% zinc and 65% copper and is used for musical instruments, jewellery, faucets and decorative hardware.
 Stainless steel is mostly iron, plus more than 11% chromium, and various amounts of nickel and carbon and is used for tableware, cookware and surgical tools.
 Steel is made of 99% iron and 1% carbon and is used for tools, car bodies, machinery, girders and rails.
 Bronze is made of mostly copper and some tin and is used for boat hardware, screws and grill work.
 Alnico is a mix of aluminium, nickel and cobalt, and it is used to make permanent magnets.

 
Metallurgy
Material is what everything that you can touch is made of. Even material that is too small to touch, is called material. We use materials to make things. We can also call material "physical substances."

Raw material is materials such as ores which we can clean and mix with other materials to make another material like steel, for example. Cotton is a raw material used to make textiles, which are materials to make clothes.

Some important materials

 Metals
 Steel
 Aluminum
 Copper
 Gold
 Polymers
 Rubber
 Plastic
 Ceramics
 Glass
 Cement
 Stone
 Textiles
 Cotton fabric
 Wool fabric
 organic materials
 Leather
 Bone
 Paper
 Lumber/wood
 Glue
 Composites
 Fiberglass
 Concrete
A neuron (or neurone) is a nerve cell that carries electrical impulses. Neurons are the basic units of our nervous system. 

Neurons have a cell body (soma or cyton), dendrites and an axon. Dendrites and axons are nerve fibers. There are about 86 billion neurons in the human brain. Almost all brain cells are neurons. The human brain has about 16 billion neurons in the cerebral cortex. The neurons are supported by glial cells and astrocytes.

Neurons are connected to one another, but they do not actually touch each other. Instead they have tiny gaps called synapses. These gaps are chemical synapses or electrical synapses which pass the signal from one neuron to the next.

Neuron ( link )

Types of neurons

By connection 
There are three classes of neurons: motor neurons, sensory neurons and interneurons.
 Sensory neurons carry information from tissues and organs into the central nervous system.
 Motor neurons transport signals from the central nervous system to the effector cells.
 Interneurons connect neurons within the central nervous system.

By function 
Sensory neurons carry signals from sense organs to the spinal cord and brain.
Relay neurons carry messages between sensory or motor neurons and the central nervous system
Motor neurons carry signals from the CNS to muscles, motor neurons are connected to the relay neurons. The signal passes between the neurons via synapses. Synapses are microscopic voids between cells where chemicals are released from the axon terminal of one cell to specialized chemical receptors on the dendrite of the receiving cell.

Cell division 
Mature neurons never divide: that is the general rule. They do not undergo cell division. In most cases, neurons are generated by special types of stem cells. A type of glial cell, called astrocytes, have also been seen to turn into neurons. In humans, neurogenesis (the origin of new nerve cells) largely ceases during adulthood  but in two brain areas, the hippocampus and the olfactory bulb, there is strong evidence for substantial numbers of new neurons.

The largest part of the human brain by far is the neocortex. It has at least ~1010 (10 trillion) neurons which stay with us from birth to death.

References

Related pages 
Brain cell

Other websites 
 Fibrinogen found to inhibit EGFR in neuronal cells Blood clotting protein may inhibit spinal cord regeneration 
 Cell Centered Database  UC San Diego images of neurons.
 High resolution neuroanatomical images of primate and non-primate brains .

Anatomy of the nervous system
Cells
The Middle East is a large area of land in the eastern hemisphere. The lands of the Arabian Peninsula and some of the lands of the eastern Mediterranean are part of the Middle East. The Middle East's population is mostly Muslim. The name of the Middle East comes from its position to the east of Europe and to the west of the Far East. 

It is normal for the modern countries of Arabia (Saudi Arabia, Oman, Yemen, Bahrain, Jordan, Kuwait, and the United Arab Emirates) to be counted with the modern countries of  Iraq, Syria, Lebanon, and Palestine (the State of Palestine and Israel) as part of the Middle East.

The name "Middle East" does not always have the same meaning, and the size of the area is not always the same. When the name Middle East started to be common, it was the name for the lands in between the Near East and the Far East. The Indian subcontinent was part of the Middle East at that time. Now, parts of south-west Asia and northern Africa can count as the Middle East. The land between Egypt and Iran is a common definition. Many countries in the Middle East today are also part of the Near East. Sometimes, people name countries that are far away from these countries as countries in the Middle East. These countries can be in North Africa (like Morocco) and the Indian subcontinent (like Pakistan). This area also has the name Greater Middle East.

Many ancient civilizations began in the Fertile Crescent in the Middle East. These were Sumer, Babylonia and Assyria in the area called Mesopotamia. The Abrahamic religions that believe in one God also started in the Middle East. (Judaism and Christianity began in ancient Palestine and Islam began in Arabia.) Today, the Middle East is the homeland of Arabs, Turks, Persians, Kurds, and Jews, among many other ethnic groups. Islam is the most common religion in the Middle East. Islam came to most of the Middle East's lands in the 7th century AD, during the first Muslim conquests of the Sasanian Empire and of the Roman Empire's lands.

Today, the Middle East is very important because much of the petroleum that other countries use comes from here. There are also many arguments and wars, such as the conflict between Sunni and Shia, the Israeli–Palestinian conflict, and the Syrian civil war.

Related pages 

 Western Asia
 Central Asia
 East Asia
 South Asia
 Southeast Asia

References
Warsaw (In Polish: Warszawa) is the capital of Poland in Masovian Voivodeship. It is also the biggest city in that country. There are about 2,000,000 people living there (1,726,581 as of 31 March 2014). People from Warsaw are called "Varsovians".

There are other names for Warsaw. For example,  (Latin, Spanish) and Varsóvia (Portuguese),  (French),  (Italian),  (German, Dutch),  /Varshe (Yiddish),  (Lithuanian),  (Hungarian) and Varšava (Czech)

Geography 
Warsaw is near the middle of Poland on both sides of the Vistula river, and about 350 km (225 miles) from the Baltic Sea. It is about 100 m (325 ft) above sea level. Warsaw has a humid continental climate (Dfb in the Koeppen climate classification).

Warsaw is home to four universities and 62 colleges, and many theatres and art galleries.

History 
People began living here in the 13th century. By the 15th century, Warsaw had grown enough to be called a city. It became the capital of Poland in 1596.

The city was destroyed several times in its history, but every time it was rebuilt. The most important of these times was during the Second World War. Poland had been occupied by Germany between 1939 and 1944. On 1 August 1944, the people of Warsaw started fighting to free their city.

Tourist attractions 
There are lot of attractions in the capital of Poland. The most famous monument of Warsaw is Palace of Culture and Science. There is a palace in Wilanów. The king of Poland John III Sobieski lived there. Many people like going to the Museum of Warsaw Uprising. The uprising started in 1944 during World War II

Partner cities 
-Athens, Greece

-Chicago, USA

- Rio de Janerio, Brazil

- The Hague, The Netherlands

Pictures of Warsaw

References

Other websites 

 Official web page of Warsaw 
 Official tourist web page of Warsaw 
 Interactive city map 
 Modern architecture in Warsaw 
 Historic images of Warsaw
The Hindu–Arabic numeral system, sometimes known as Hindu–Arabic numbers, is the system of numbers used by almost all the world today. It is a positional notation system. This system has ten basic symbols, they are 0, 1, 2, 3, 4, 5, 6, 7, 8 and 9. It represent numbers in the decimal number system. The Hindu–Arabic numeral system was first developed by the Hindus. Later, It was introduced to the western world by the Arabs. The Hindu–Arabic numeral system is one of the few numeral systems that use a place value system. This system is now commonly used all over the world.

They originated in India in the 6th or 7th century and were introduced to Europe through the writings of Middle Eastern mathematicians, especially al-Khwarizmi and al-Kindi, about the 12th century.  They are very different from previous methods of counting, such as the abacus, and paved the way for the development of algebra.  In the past many other systems were used. Fibonacci popularized the Hindu–Arabic numeral system to the Western World.

References 

Mathematics
Numerals
A point is a precise position in space. Imagine touching a piece of paper with a sharp pencil or pen, without making any sideways movement. We know where the point is, but it has no size to speak of.

In geometry, a point has no size, but has a position. This means it has no volume, area or length. We usually represent a point by a small cross 'X' or by a small dot (a small, round shape). Points are always labelled by capital letters (A, B, C...X, Y, Z). It is one of the most fundamental but undefined terms in geometry.

In general, two points can be:
 Coincident (they are one and the same)
 Not coincident (they are not one and the same)
and are always:
 Coplanar (on the same plane)
 Colinear (on the same line)
 Concyclic (on the same circle)

Three points can be:
 Colinear
 Coincident
 Not coincident
 Not colinear
and are always:
 Coplanar
 Concyclic

Four points can be: 
 Coplanar
 Colinear
 Coincident
 Not coincident
 Not colinear
 Not coplanar

Related pages 

 Line
 Plane

References 

Geometry
A line is the path of one point moving. A line has length but no width. A line is a type of geometric figure.

A line is made up of an endless number of points.

Straight and curved lines 

A line can be straight or curved. In geometry, the word line means a straight line. A straight line is the shortest distance between two points. A straight line is the line traced by a point moving in a direction that does not change.

A curved line is sometimes called a curve. The edge of a circle is not straight and is an example of a curve.

Line segments 
A line segment is part of a line. Here is an example of a straight line segment:

Naming lines 
Lines can get their names from any two points on the line. For example, if a line contains two distinct points, named  and , then the line can be called either , or .

Sometimes, lines are also named with just one symbol. In which case, a letter such as  might be used.

Two lines 
Two lines can be:
 Parallel: Two lines are parallel if they are on the same plane and they never touch.
 Concurrent: Two lines are concurrent if they touch on one point.
 Coincident: Two lines are coincident if they are made of the same points.
 Perpendicular: Two lines are perpendicular if they make four right angles where they touch.
 Skew: In Euclidean space, two lines are skew if they are not parallel but they never touch.

Related pages
 Linear function
 Point (geometry)
 Plane (mathematics)

References 

Basic English 850 words
Geometry
A plane is a perfectly flat surface extending in all directions. It can be thought of as the ceiling of a room, only extended into all directions infinitely. A plane has two dimensions: length and width. All planes are flat surfaces. If a surface is not flat, it is called a curved surface. 

The tool plane can be used to create a flat, level surface like the mathematical plane—hence the name.

In geometry, a plane is made up of an infinite number of lines (or points). It has no depth. It is absolutely flat and infinitely large.

A plane figure is part of a plane. It is named by the capital letters (such as A, B, C, ...X, Y, Z) that are put at its corners. Sometimes, a single capital pi  is also used to refer to a plane. A plane can also be named after three points that are not all on the same line.

In general, two planes can be:
 Parallel (they never meet)
 Concurrent (they meet forming a line)
 Coincident (they are one and the same)

Plane in mathematics 

In mathematics, a plane is a fundamental two-dimensional object. Intuitively, it looks like a flat infinite sheet of paper. There are several definitions of the plane. They are equivalent in the sense of Euclidean geometry, but they can be extended in different ways to define objects in other areas of mathematics. The only two-dimensional figure in our three-dimensional world is a shadow.

In some areas of mathematics, such as plane geometry or 2D computer graphics, the whole space in which the work is carried out is a single plane. In such situations, the definite article is used: the plane. Many fundamental tasks in geometry, trigonometry and graphing are performed in the two dimensional space, or in other words, in the plane.

Euclidean geometry 
 	
A plane is a surface such that, given any three distinct points on the surface, the surface also contains all of the straight lines that pass through any two of them.
One can introduce a Cartesian coordinate system on a given plane in order to label every point on it with a unique ordered pair, which is composed of two numbers and is the coordinate of the point.

Within any Euclidean space, a plane is uniquely determined by any of the following combinations:

 Three points which are not lying on the same line
 A line and a point not on the line
 Two different lines which intersect
 Two different lines which are parallel
 A vector normal to the plane and a distance from the origin

Related pages
 Point (geometry)
 Line

References

Other websites 
 Mathworld: Plane
 Easing the Difficulty of Arithmetic and Planar Geometry (work in Arabic, description in English)

Shapes
Geometry
When two straight lines come together, they make an angle. The two lines are called the sides of the angle, and they meet at a point. A flat surface (called a plane) also forms an angle when it meets another.

To represent an angle, Greek letters such as  (alpha),  (beta),  (gamma) and  (theta) are sometimes used. An angle indicates the space between its sides, or the amount of rotation needed to make one side coincide the other.

To measure the size of an angle, we use units called degrees. A degree is a standard unit and we use the symbol ° after a number to show that it is a number of degrees. We can use a decimal number or a fraction for part of a degree, but a degree can also be divided into 60 minutes (1° = 60'), and a minute can be divided into 60 seconds (1' = 60"). So 22.5°, 22° and 22° 30' are all the same angle.  

In mathematics, angles can also be (and often are) measured in radians instead of degrees, by using the conversion factor  (for example, ). Yet another unit of angle is gradian, with  . 

Angles are studied in geometry, where an angle where edges meet is often called a vertex. For example, the three sides of a triangle are its edges and two of the edges meet at each vertex. Similarly, two of the six sides (or faces) of a cube meet at each of its twelve edges, and three edges meet at each of its eight corners (or vertices, which is the plural version of vertex).

Types of angles

 In a zero angle the lines lie one upon the other thus creating a 0° angle aka the zero angle.

 An angle greater than 0° but less than 90° is called an acute angle.

 An angle of 90° is called a right angle.

 An angle greater than 90° but less than 180° is called an obtuse angle.

 An angle that measures 180° is called a straight angle.
 An angle greater than 180° and less than 360° is called a reflex angle.
 An angle that has a made or full circle/ completed 360° is called a  full or complete angle.

Supplementary angles are two angles with the sum equal to 180°, and complementary angles are two angles with the sum equal to one right angle (90°). On the other hand, two angles that sum to one full circle (360°) are sometimes called explementary angles, or conjugate angles.

People usually use a protractor to measure and draw angles. Sometimes, people use a 360° protractor to measure angles.

Related pages 

 Sun angle

References

 
 
 
Basic English 850 words
An astrophysicist is a person whose profession is astrophysics.

Canada
 Hubert Reeves, is known for  explaining science to the general public (or popularizing science).

Great Britain

England
 Stephen Hawking, is known for Hawking radiation, Penrose–Hawking theorems, Bekenstein–Hawking formula, Hawking energy, Gibbons–Hawking ansatz, Gibbons–Hawking effect, Gibbons–Hawking space, Gibbons–Hawking–York boundary term, Thorne–Hawking–Preskill bet

United States

 Frank Drake, is known for developing the Drake equation, and as the creator of the Arecibo Message, a digital encoding of an astronomical and biological description of the Earth and its lifeforms, for transmission into the cosmos.

 Freeman John Dyson, is known for Dyson sphere, Dyson operator, Dyson series, Schwinger–Dyson equation, Circular ensemble,  Random matrix theory, Advocacy against nuclear weapons, Dyson conjecture, Dyson's eternal intelligence, Dyson number, Dyson tree, Dyson's transform

 Neil deGrasse Tyson, is known for being on a 2001 government commission on the future of the U.S. aerospace industry, and on the 2004 Moon, Mars and Beyond commission; got the NASA Distinguished Public Service Medal; host of television show NOVA ScienceNow on PBS

Related pages
List of astronomers

Lists of scientists
Some vegetables which are botanically fruits (such as tomatoes) are considered to be vegetables in the culinary (eating) sense. This is why they appear in this article. For sources, see individual pages.

artichoke
aubergine (eggplant)biologically a fruit but taxed as a vegetable 
 asparagus
legumes 
alfalfa sprouts
azuki beans (or adzuki)
bean sprouts
black beans
black-eyed peas
borlotti bean
broad beans
chickpeas, garbanzos, or ceci beans
green beans
kidney beans
lentils
lima beans or butter bean
mung beans
navy beans
peanuts
pinto beans
runner beans
split peas
soy beans
peas
mange tout or snap peas
broccoflower (a hybrid)
broccoli (calabrese)
brussels sprouts
cabbage
kohlrabi
Savoy cabbage 
red cabbage
cauliflower
celery
endive
fiddleheads 
frisee
fennel
greens
bok choy
chard (beet greens)
collard greens
kale
mustard greens

herbs 
anise
basil
caraway
coriander 
chamomile
daikon
dill
fennel
lavender
cymbopogon (also known as lemongrass)
marjoram
oregano
parsley
rosemary
thyme
lettuce 
arugula
mushrooms (actually a fungus, not a plant)
nettles
New Zealand spinach
okra
onions
chives
garlic
leek 
onion
shallot
scallion (spring onion UK, green onion US)
peppers (biologically berry, but taxed as vegetables)
bell pepper
chili pepper
jalapeño
habanero
paprika
tabasco pepper
cayenne pepper
radicchio
rhubarb
root vegetables
beetroot (UK) beet (US)
mangel-wurzel: a variety of beet used mostly as cattlefeed
carrot
celeriac
corms
eddoe
konjac
taro
water chestnut
ginger
parsnip
rutabaga
radish
wasabi
horseradish
 daikon or white radish
tubers
jicama
jerusalem artichoke
potato
sweet potato
yam
turnip
salsify (Oyster Plant)
skirret
sweetcorn 
topinambur
squashes (biologically fruits, but taxed as vegetables)
acorn squash
bitter melon
butternut squash
banana squash
courgette (UK), Zucchini (US)
cucumber (biologically fruits, but taxed as vegetables)
delicata
gem squash
hubbard squash
marrow (UK) Squash (US)

spaghetti squash 
zucchini 
spinach
tat soi
tomato (biologically a fruit, but taxed as a vegetable.)
watercress

References

Other websites 
 Lists of vegetables
Vegetables Name List 

Food-related lists
Astronomical telescopes are divided into subgroups. All telescopes work by collecting electromagnetic radiation and focussing it into an image which may be seen or photographed. The purpose is to see things which are far away in the universe.

The traditional types all work to collect visible light from the sky. Recent types may work outside the visible spectrum. They all have their different advantages and disadvantages and they are used in different areas of astronomy.

Optical

Refractors 
Dioptrics.
Telescopes which create their image with an objective that is a convex lens (refractors) are said to be "dioptric" telescopes.
 Achromatic: uses convex and concave lenses together, to correct for chromatic aberration.
 Apochromatic: a more complex arrangement, for even less chromatic aberration.
 Non-achromatic
 Binoculars

Reflectors 
Catoptrics.
Optical systems using mirrors: uses reflected light to form the image.
 Newtonian
 Gregorian
 Cassegrain
 Herschelian telescope

Combined Lens-Mirror Systems 
Catadioptric telescopes use corrector lenses to fix problems in a reflector.
 Schmidt telescope
 Maksutov telescope

Outside the optical spectrum 

 Čerenkov radiation telescope used to detect gamma rays
 Infrared telescope
 Radio telescope
 Submillimeter telescope
 Ultraviolet light telescope (for Ultraviolet astronomy)
 X-ray telescope (for X-ray astronomy)
Wolter telescope

!
Astronomy lists