Aarushhh/wikipedia-simple-splitted huggingface dataset:
Glass can be recycled over and over. Glass bottles and jars can easily be recycled to make new glass bottles and jars or used in industry as aggregate (building material) or sand.

References

Other websites 

 Corning Museum of Glass
 A comprehensive guide to art glass and crystal around the world
 Working Description Furnace & Moleria - Murano Glass
 Informative website about the glass industry
 Substances used in the Making of Colored Glass 
 Almost 400 articles and images about glass (mostly art glass)

 
Basic English 850 words
God is a being or spirit worshipped as a deity. He is considered to be the creator of the universe in some religions. Theists believe that God created everything that exists and has ever existed. Some theists think God is immortal (cannot die) and has power without limits.  Deism is the belief that God exists, but God does not very often change or never changes things in the universe.  Pantheism is the belief that the universe is God, while atheism is the belief that there are no deities. Agnostics think we cannot know for sure whether God or gods exist, but still might (or might not) believe at least one deity exists.  People who believe that the word "God" should be defined before taking a theological position are ignostic.
In some religions, there is only one deity, God. This is called monotheism. Some monotheistic religions are the Abrahamic religions (Christianity, Judaism, and Islam), the Bahá'í Faith, and Sikhism. In other religions there are many gods. This is polytheism. Some polytheistic religions are Hinduism, Shinto, Taoism, paganism, Wicca and some variants of Buddhism. Some say that there is one God who can come in many forms, or that there is one God that is more powerful than the other gods. 

In philosophy and theology, people normally write about a God that has a personality but no body and is everywhere at once; that God made the world and time and is separate from the world; that no-one made God; that God knows everything and has all power; that God is both free and good; and that God is perfect and the start of all morality.
There are different names for God in different religions. Some examples are Yahweh, Elohim in Judaism and Christianity, Allah in Islam, Baha in Bahá'í Faith, and Ahura Mazda in Zoroastrianism.

In English, people write the words "god" and "gods" are in lowercase letters. People that believe in only on god (monotheists) like to write God with a capital letter. Some people that believe in more than one god (polytheists) also like to use capital letters when writing about their gods. Most people that believe in God or gods do not believe in the gods of other religions.

Does God exist? 
Many people have asked themselves if God exists. Philosophers, theologians, and others have tried to prove that it exists. Others have tried to disprove the hypothesis. In philosophical terminology, such arguments are about the epistemology of the ontology of God. The debate exists mainly in philosophy, because science does not address whether or not supernatural things exist.
There are many philosophical issues with the existence of God. Some definitions of God are not specific. Arguments for the existence of God typically include metaphysical, empirical, inductive, and subjective types. Some theories try to explain order and complexity in the world without evolution or scientific method. Arguments against the existence of God typically include empirical, deductive, and inductive arguments. Conclusions sometimes include: "God does not exist" (strong atheism); "God almost certainly does not exist" (de facto atheism); "no one knows whether God exists" (agnosticism); "God exists, but this cannot be proven or disproven" (deism or theism); and "God exists and this can be proven" (theism). There are many variations on these positions, and sometimes different names for some of them. For example, the position "God exists and this can be proven"  is sometimes called "gnostic theism" or "strong theism".

Believing in God
Believing in God 

By the year 2000, approximately 53% of the world's population were part of one of the three main Abrahamic religions (33% Christian, 20% Islam,  less than 1% Judaism), 6% with Buddhism, 13% with Hinduism, 6% with traditional Chinese religion, 7% with various other religions, and less than 15% as non-religious. Most of these religious beliefs involve God or gods. Some religions do not believe in a god or do not include the concept of gods.

God in the Abrahamic religions 
Abrahamic religions are very popular monotheistic ones. Well-known Abrahamic religions include Judaism, Christianity, and Islam. Monotheistic means the people in these religions believe there is only one God. The name of God is usually not allowed to be said in Judaism, but some Jews today call him YHWH (Yahweh) or Jehovah. Muslims say the word Allah, which is the Arabic word for "God".
Believers in the Abrahamic religions (except Islamic believers) believe that God has created human beings in his image, but this idea is not easily understood by humankind. One artistic idea is that of an wise elder man in use since the Renaissance.

God in Christianity 

The Christian Bible talks about God in different ways. Within Christian canon the Old Testament talks about "God the Father", whilst the Gospels in the New Testament are about Jesus, or "God the Son". Many Christians believe that Jesus was God's incarnation on Earth. Christians consider the  Holy Spirit to be God as well, the third person of God.
In the New Testament, there are three beings who are said to be God in different forms: the Father, the Son, and the Holy Spirit (also known as the Holy Ghost). This is called the Trinity. Although the word "Trinity" is not in the Bible, the word used for God in chapter one of Genesis is actually plural, and the phrase "in the name of the Father, Son and Holy Spirit' is used in the New Testament, (e.g. Matthew 28:19). Another word that Christians believe has exactly the same meaning as "Trinity" is the word "Godhead", which is in the Bible.
Jesus also taught that one must be born again in order to receive God's Spirit, otherwise one remains separated from God, acting merely from their own mind, thus being vulnerable to deception by human philosophies or the many spiritual philosophies which do not come from God but from fallen angels, which are within various false religions. After a person consciously accepts the free gift of eternal life, which Jesus's sacrifice offers, God comes to live in the individual, as God lived in humankind before the Fall.

God in Eastern religions 
In Hinduism, there is only one God, named Brahman, but Brahman is said to have taken on many different incarnations. Some of these are Rama, Krishna, Buddha, Shiva, Kali, Parvati, and Durga. To many outsiders, the worship of God's different incarnations is considered to be the worship of many gods. However, it is really only the worship of one God in different ways.
Some Hindus also believe that the spirit of God lives in everyone. This idea is called Advaita Vedanta, which is the Hindu term for Monism.

Religions like Buddhism and Confucianism involve the worship of many gods, or sometimes no gods at all.

In Shinto, there is not a single specific God, as is in most religions, but instead, a wide variety of deities called kami, they are the spirit and essence of all nature things, both animate and inanimate, even including rocks, trees and poetry, for example. As Shinto is a  polytheistic religion, it is usually believed that there are eight-million Kami (八百万の神 yaoyorozu-no-kami), in the Japanese language, the number "eight-million" is normally used to mean infinity.

God in Western philosophy 
Philosophers can talk about God or god; sometimes they talk about a specific god, but other times they are just talking about the idea of god.
One of the earliest Western philosophers to write about God in a monotheistic way was the Greek Aristotle, who describes god as the Supreme Cause. Aristotle saw God as a being that makes everything happen, but is not influenced by anything else.

The idea of an "all powerful" God raises some interesting questions. One of them is called the God paradox. It asks whether God can make a mountain (or rock) that is so heavy he cannot lift it. The question considers if a god "who can do anything" could do two things that are mutually contradictory.
There have been several attempts to prove the existence of God with logic. Blaise Pascal said that it is better to believe there is a god, than to believe there isn't. This argument is known as Pascal's wager today. Note that Blaise Pascal was a mathematician, and he used this argument to illustrate the concept of expected value in statistics. Other attempts known as the ontological argument, the cosmological argument, and teleological argument today. Kurt Gödel formulated an argument for the existence of God using modal logic in the 1970s.

Related pages
Cosmogony
Deity
Thomas Aquinas
Immanuel Kant

References 

Gods and goddesses
In folklore, a ghost is thought to be the spirit of a dead person which tried very much to scare us or they are referred to as the supernatural by others. Scientists say that there are no real ghosts, but many people believe that there are. There are a huge amount of stories about ghosts in books and movies. Sometimes the ghost is the spirit of a person who was killed by someone or who was already dead. 

The ghost may stay on Earth because he or she has unfinished problems or is still trying to say goodbye to people who they missed. Sometimes ghosts are said to live in a particular locality, for example an abandoned house or a place that existed hundreds of years ago.
Sometimes the ghosts in these stories exist because of some problem the person had during life or to say goodbye to loved ones, that was not solved before he or she died. The ghost stays on Earth trying to fix the problem. If the problem is fixed, the ghost can leave. Many people say they have seen or heard ghosts. People who try to talk to ghosts as their job are called mediums.

There can be bad ghosts and there can also be good ones. There have never been any ghosts that have actually hurt or killed people, although people tell stories about it.
Many people believe they have seen ghosts. Others believe they have felt ghosts near them. Often the ghost is said to appear as a feeling of cold and a light or a misty cloud, but sometimes people say they have seen ghosts that look more like people. Sometimes ghosts are said to come in human form. Some ghosts might cause fear in the person who sees them, by being seen suddenly. Some ghosts are said to be friendly and help people who have problems. People or animals that can sense ghosts cannot feel them touching them as they are the spirit of a person, or a personified force.

Ghosts are said to form right after people die, or even centuries later. Many people make up stories or urban legends. Many try to prove the existence of these paranormal creatures with special technology such as heat sensors. They also make TV shows dedicated to proving the existence of ghosts. They often investigate cases where a person has seen one or visit a place of sighting.
Stories of ghosts can be found all over the world. Chinese philosopher Confucius said "Respect ghosts and gods, but keep away from them."

The most feared spirit in Thailand is Phi Tai Hong, the ghost of a person who has died suddenly of a violent death. The Koran discusses spirits known as jinn. In Europe there is the recurring fear of "returning" or revenant deceased who may harm the living. This includes the Scandinavian , the Romanian , the Serbian vampir, the Greek vrykolakas among others.

Modern times 

In modern days, ghosts have become common features in horror and fantasy stories. Their appearance can take the form of the person they once were or sometimes they are depicted wearing white cloaks over their body and face.

At Halloween, many people dress up as ghosts.

Related pages 
Spiritual séance

References

Other websites
Other websites 

 Ghost and the musical traditions within the County of Nice, France
 Ghostsandstories.com Ghost stories and haunted places.
 Your Ghost Stories People sharing their ghost experiences.

Occult
Afterlife
Green is a color between the yellow and blue colors in the rainbow. Green is a primary color (a color that can be mixed with another color) of light. The others are red and blue. 

Green and blue are next to each other on the spectrum, and there are languages which do not distinguish between them. Examples are old Chinese, Thai, old Japanese, and Vietnamese. 

Green paint can be made by mixing yellow paint and blue tempera paint together. 

Green light, like all light, is quanta—composed of photons. The wavelength of green light is about 550 nanometers (one-billionth of a meter).

Most leaves of growing plants, such as trees and bushes, are green. This is because there is a chemical in leaves, called chlorophyll, which is colored green.

See color vision for more on the significance of green.

Meaning of green 
 Green is used as a color associated with jealousy. The phrase "green-eyed monster" means a jealous person.
The color green is the color of nature. Having a "green thumb" means that you're good at gardening.

Green is a color associated with poison. Paris green is a highly toxic chemical compound.

Green is a color of the Islamic religion. Search the shade "Islamic Green" below.

 Green is also the color of sickness. The phrase "green around the gills" is an expression implying that the person is nauseated.

Comparison of green, teal, blue and ultramarine

Tones of green color comparison chart 
Green is a color, the perception of which is evoked by light having a spectrum dominated by range with a wavelength of roughly 570-520 nm.

Related pages

 Color vision
 List of colors
 Chartreuse green
 Emerald green
 Erin
 Fruitamins
Grape
Gray-green
Harlequin green
 Kiwi green
 Lime green
 Mint green
 Olive green
 Parrot
 Spring green
 Sweet Lime green
 Viridian

References

Basic English 850 words
God's eye view is a name for a point of view where the speaker or writer assumes he or she has knowledge only God would have. It appears several ways:

In religion, when an institution claims to speak for a divine being.

In writing, when a writer leaves the point of view of the main actor to start writing about things they could not know if the story were in real life.

In science, when a scientist ignores the way a subject-object problem affects statistics or an observer effect affects experiment.

In medicine when a doctor makes a claim that The Gaze they use on a patient, actually sees the problem, rather than making a guess at a problem.

In ethics when a statement is made about who or what is right, without an honest attempt to make the process of deciding this consider all points of view.

A special case of the last is in a wiki with a GodKing.  Often this person can get others to believe what they say about what is right, without making any special effort to be fair to other views.
Many people think René Descartes took a God's eye view when he said cogito ergo sum.  George Berkeley argued that optics from Isaac Newton and Johannes Kepler also had this problem.

Social sciences
Google LLC is an American multinational corporation from the United States. It is known for creating and running one of the largest search engines on the World Wide Web (WWW). Every day more than a billion people use it. Google's headquarters (known as the "Googleplex") is in Mountain View, California, part of Silicon Valley. The motto of Google is "Do the right thing".

Since September 2, 2015, Google has been owned by a holding company called Alphabet Inc.. That company has taken over some of Google's other projects, such as its driverless cars. It is a public company that trades on the NASDAQ under the ticker symbols GOOG and GOOGL.
Google's search engine can find pictures, videos, news, Usenet newsgroups, and things to buy online. By June 2004, Google had 4.28 billion web pages on its database, 880 million pictures and 845 million Usenet messages—six billion things. Google's American website has an Alexa rank of 1, meaning it is the most widely visited website in the world. It is so widely known that people sometimes use the word "google" as a verb that means "to search for something on Google". Because more than half of people on the web use it, "google" has also been used to mean "to search the web".

History 
Larry Page and Sergey Brin, two students at Stanford University, USA, started BackRub in early 1996. They made it into a company, Google Inc., on September 7, 1998, at a friend's garage in Menlo Park, California. In February 1999, the company moved to 165 University Ave., Palo Alto, California, and then moved to another place called the Googleplex.
In September 2001, Google's rating system (PageRank, for saying which information is more helpful) got a U.S. Patent. The patent was to Stanford University, with Lawrence (Larry) Page as the inventor (the person who first had the idea).

Google makes a percentage of its money through America Online and InterActiveCorp. It has a special group known as the Partner Solutions Organization (PSO) which helps make contracts, helps to make accounts better and gives engineering help.
Advertising 
Google makes money by advertising. People or companies who want people to buy their product, service, or ideas give Google money, and Google shows an advertisement to people Google thinks will click on the advertisement. Google only gets money when people click on the link, so it tries to know as much about people as possible to only show the advertisement to the "right people". It does this with Google Analytics, which sends data back to Google whenever someone visits a website. From this and other data, Google makes a profile about the person and then uses this profile to figure out which advertisements to show.

Branding 
The name "Google" is a misspelling of the word googol. Milton Sirotta, nephew of U.S. mathematician Edward Kasner, made this word in 1937, for the number 1 followed by one hundred zeroes (10100). Google uses this word because the company wants to make lots of stuff on the Web easy to find and use. Andy Bechtolsheim thought of the name.
The name for Google's main office, the "Googleplex," is a play on a different, even bigger number, the "googolplex", which is 1 followed by one googol of zeroes 1010100.
Products 
 Android is an operating system for mobile devices and was originally made by Google as part of the Open Handset Alliance, which Google leads. It is the chief competitor to Apple's iOS and Windows Phone by Microsoft (now discontinued).
 Google Adsense is a free program that enables website publishers of all sizes to display relevant Google ads and earn money.
 Google Analytics is the enterprise-class web analytics solution that gives one rich insights into his website traffic and marketing effectiveness.
 Google Alerts Google Alerts are email updates of the latest relevant Google results (web, news, etc.) based on one's choice of query or topic.
 Google Allo was software for discussing with other people live.
 Google Assistant is a virtual assistant application built into Android devices.
 Blogger is a free tool that allows users to publish blogs on a Google website.
 Google Books lets people search for books.
 Google Calendar is an online calendar.
Google Chrome is a web browser that Google made.
Google Classroom is an online system for students. It was popular during COVID-19.
 Google Docs is an online Google full of docs.
 Google Drive is an online document editor.
 Google Earth is the 3D version of Google Maps with a digital globe.
 Google Groups is a place for users to discuss topics. Google bought Deja News in 2001 and made it into Google Groups.
 Google Images is an image search utility.
 Google Maps is a service from Google to provide satellite pictures and road maps for everywhere around the world.
 Google News is a facility which shows news stories from over 4,500 news sources. Google News Archives
 Google Pay is a way to pay online. Users can send money using their credit cards or bank accounts to other users.
 Google Photos is a software for organizing and editing photos.
Google Play is a sector that has games, and other things.
 Google Products is a pack of Google software.
 Google Search is a search utility.
Google Shopping lets the user find out about things for sale on the Internet.
 Google Translate is an online translation service. It can translate websites and text into other languages.
 Google Sites is a service for making websites.
 Google Video is a video search utility.
 Google+ was a social networking service that is like Facebook. The service launched on June 28, 2011.
 Gmail is an e-mail service that Google started in 2004. It is called Google Mail in the United Kingdom and Germany. Users get free space to store e-mail.
 Hangouts is an instant messenger where one can talk to friends. It ended up shutting down on November 1, 2021.
 Sidewalk Labs
 Tenor is a search utility for GIF files
 Waze is a navigation service that gives driving directions.
YouTube is a video hosting service which was bought by Google from PayPal for 1.65 billion dollars and now runs as a Google service.
References 

Notes

Other websites 

 
 The search engine
 
 

 
1998 establishments in the United States
Companies listed on NASDAQ
Mountain View, California
Search engines
Companies based in California
A gallon is a volumetric unit of measurement. People have used many different gallons throughout history. Only two gallons are still commonly used, which are the imperial and U.S. liquid gallon.This is 3,57 liter

Sale of petrol 
Petrol, also known as gasoline, is sold by the imperial gallon in four British Overseas Territories (Anguilla, the British Virgin Islands, the Cayman Islands, and Montserrat) and six countries (Antigua and Barbuda, Dominica, Grenada, Saint Christopher and Nevis, Saint Lucia, and Saint Vincent and the Grenadines). All of the countries and territories just mentioned also use miles per hour for speed limits and drive on the left side of the road.

Gasoline is sold by the U.S. gallon in Belize, Colombia, Dominican Republic, Ecuador, Guatemala, Haiti, Honduras, Liberia, Nicaragua, and Peru, as well as in the Marshall Islands, Federated States of Micronesia, and Palau.

Sizes

References

Imperial units
Units of volume
A government is a group of people that have the power to rule  in a territory, according to the administrative law. This territory may be a country, a state or province within a country, or a region. There are many types of government, such as democratic, parliamentary, presidential, federal or unitary.
Works
Governments make laws, rules and regulations, collect taxes and print money. 
Governments have monopolies on the legal use of force.
Governments have systems of justice that list the acts or activities that are against the law and describe the punishments for breaking the law. 
Governments have a police force to make sure people follow the laws. 
Governments have diplomats who communicate with the governments of other countries by having meetings. Diplomats try to solve problems or disagreements between two countries, which can help countries to avoid war, make commercial agreements, and exchange cultural or social experiences and knowledge. 
Governments have a military force such as an army that protects the country from terrorists and other major threats that attack or which can be used to attack and invade other countries. 
The leader of a government may have advisors and ministers for various departments. Together they are called the administration.
Types of governments 
Plato listed five kinds of government in The Republic:

Democracy 
The most common type of government in the Western world is called democracy. In democracies, people in a country can vote during elections for representatives or political parties that they prefer. The people in democracies can elect representatives who will sit on legislatures such as the Parliament or Congress. Political parties are organizations of people with similar ideas about how a country or region should be governed. Different political parties have different ideas about how the government should handle different problems. Democracy is the government of the people, by the people and for the people.
However, many countries have forms of democracy which limit freedom of choice by the voters. One of the most common ways is to limit which parties can stand for parliament, or limit the parties' access to mass media such as television. Another way is to rig (unfairly manipulate or interfere with) the voting system by removing votes from opposition voters and substituting votes for the party in power. Few countries are textbook (classic, paradigmatic) democracies, and the differences between them has been much studied.

Monarchy 
A monarchy is a government ruled by a king or a queen who inherits their position from their family, which is often called the "royal family." There are two types of monarchies: absolute monarchies and constitutional monarchies. In an absolute monarchy, the ruler has no limits on their wishes or powers. In a constitutional monarchy a ruler's powers are limited by a document called a constitution.
In modern times, monarchies still exist in Great Britain and the Commonwealth, the Netherlands, Spain, Japan, Saudi Arabia, and Thailand, along with several other countries. A monarch may have one of several titles: King or Queen, Emperor or Empress, or Emir.

Aristocracy 
An aristocracy is a government run by the people of a ruling class, usually people who come from wealthy families with a particular set of values, or people who come from a particular place. A person who rules in an aristocracy is an aristocrat. Aristocracy is different from nobility, in that nobility means that one bloodline would rule, whereas an aristocracy would mean that a few or many bloodlines would rule, or that rulers be chosen in a different manner.

Dictatorship 
Under a dictatorship, the government is run by one person who has all the power over the people in a country.  A dictatorship may also be called one-man rule, autocracy or tyranny.
Originally, the Roman Republic made dictators to lead during time of war.  The Roman dictators (and Greek tyrants) were not always cruel or unkind, but they did hold power all by themselves, rather than sharing power with the people.  Roman dictators only held power for a short period of time.

In modern times, a dictator's rule is not stopped by any laws, constitutions, or other social and political institutions, and can last many years or even decades. After leaving the Spanish Empire, many countries in Latin America were dictatorships. World War II was partly a war between dictators, and later new countries in Asia and Africa also were ruled by dictators. Examples of dictators include Josef Stalin, Adolf Hitler, Augusto Pinochet,  Idi Amin, Muammar al-Qaddafi, and Gamal Abdul Nasser. These men ruled from when they took power until when they died, because they would not let anyone else take power from them. There is no evidence of a woman serving as a dictator in modern times.
Oligarchy 
An oligarchy is a government ruled by a small group of powerful people. These people may spread power equally or not equally. More so a different version of a monarchy, where everyone makes decisions together instead of one person making them all or telling people what to do, such as in a Dictatorship. An oligarchy is different from a true democracy because very few people are given the chance to change things. An oligarchy does not have to be hereditary or passed down from father to son. An oligarchy does not have one clear ruler, but several powerful people. Some past examples of oligarchy are the former Union of Soviet Socialist Republics and Apartheid South Africa. A fictional example is the dystopian society of Oceania in the book Nineteen Eighty-Four. Some critics of representative democracy think of the United States as an oligarchy. This view is shared by anarchists. An oligarchy may have a leader in the ruling group.
The history and the theory of government 
The simplest idea of government is those who rule over people and land. This may be as small as a community or village or as big as a continent (like Australia and India). 

The people who rule can allow others to own land. It is a deed by government that gives this right in the way that laws describe. Some think they have the right to hold land without government permission. This view is called libertarianism. Others think they can do without government. This view is called anarchism.
Almost every place on Earth is connected to one and only one government. Places without government are where people follow traditions instead of government rules, small border disputed areas and the continent of Antarctica, because almost no people live there. For every other place on Earth there is a government that claims 'sovereign control' over it. The word "sovereign" is old and means "control by a King" (sovereign). Governments of villages, cities, counties and other communities are subordinate to the government of the state or province where they exist, and then to that of the country.

It is from Kings and feudalism that modern governments and nation states came. The capital of a country, for instance, is where the King kept his assets. From this we get the modern idea of capital in economics. A government may regulate trade as well as to rule over land.
Governments also control people and decide things about what morality to accept or punish. In  many countries, there are strict rules about sexual intercourse and drugs which are part of law and offenders are punished for disobeying them.

Tax is how government is paid for in most countries. People who buy, sell, import, invest, own a house or land, or earn money are made to pay some of the money to a government.

There are many theories of how to organize government better. These are called theories of civics. Many people think leaders must be elected by some kind of democracy. That way, they can be replaced at election. Many governments are not a democracy but other forms in which only a few people have power.

There are many theories of how to run a government better, and keep people from hurting each other. These theories are part of politics.

Related pages

 Constitution
 Horseshoe Theory
 Justice system
 Law
 Legal rights
 Local government
 Political economy
 State
 Big Government

References
References 

Basic English 850 words
A galaxy is a group of many stars, with gas, dust, and dark matter. The name 'galaxy' is taken from the Greek word galaxia meaning milky, a reference to our own galaxy, the Milky Way.

Gravity holds galaxies together against the general expansion of the universe. In effect, the expansion of the universe takes place between groups of galaxies, not inside those groups. Gravity holds the galaxy together. The same applies to  groups and clusters of galaxies, such as our Local Group where the Milky Way is, and the Virgo Cluster, a collection of more than 1,000 (might even be 2,000) galaxies. The gravitation is produced by the matter and energy in a galaxy or group of galaxies. Everything in a galaxy moves around a centre of mass, which is also an effect of gravity.
There are various types of galaxies: elliptical, spiral and lenticular galaxies, which can all be with or without bars. Then there are irregular galaxies. All galaxies exist inside the universe. The observable Universe contains more than 2 trillion (1012) galaxies and, overall, as many as an estimated  stars (more stars than all the grains of sand on planet Earth).

Description
There are galaxies of different sizes and type. Typical galaxies range from dwarfs with as few as ten million (107) stars up to giants with a hundred trillion (1014) stars, all orbiting the galaxy's center of mass. Galaxies may contain many multiple star systems, star clusters, and various interstellar clouds. The Sun is one of the stars in the Milky Way galaxy; the Solar System includes the Earth and all the other objects that orbit the Sun.
Star clusters are not galaxies, they are inside galaxies. Globular clusters are spherical-shaped star clusters which are part of the outer halo of the Milky Way. One of the largest (and oldest) known star clusters, Messier 15, has several million stars, packed closely together, with a black hole at its centre. The stars are too closely packed to get an accurate count, but it certainly has more stars than some of the smaller galaxies. 

Within galaxy clusters, galaxies move relative to other galaxies. They can and do collide. When this happens, the stars generally move past each other, but gas clouds and dust interact, and can form a burst of new stars. Gravity pulls both galaxies into somewhat new shapes, forming bars, rings or tail-like structures.
Many galaxies continue to form new generations of stars. The Milky Way, and all spiral shaped galaxies like it (see right side image of NGC 2997), produce new stars at a rate of one or two stars per year. This star formation happens in the vast interstellar clouds that account for about 1% to 10% of the mass of these galaxies. Globular star clusters, on the other hand, are not currently forming stars because this activity happened billions of years ago and then stopped once all of the gas and dust clouds were used up. 

In the astronomical literature, the word 'Galaxy' with a capital G is used for our galaxy, the Milky Way. The billions of other galaxies are written as 'galaxy' with a lowercase g. The term Milky Way first came out in the English language in a poem by Chaucer.
When William Herschel wrote his catalogue of deep sky objects, he used the name spiral nebula for objects like the Andromeda Galaxy. 200 years later astronomers discovered that they are made of stars as the Milky Way is, so the term 'nebula' is now only used for diffuse structures within a galaxy.

Types 

There are two main kinds of galaxies, spiral galaxy and elliptical galaxy. They are classified according to the Hubble Sequence.

Spiral galaxy 

A spiral galaxy is a galaxy that has a spiral shape. Most of the galaxies in the universe observed by astronomers are spiral galaxies (about 77%). 

They are divided into two :
 Barred spiral galaxy (classified as "SB")
 Unbarred spiral galaxy (classified as "SA")
NGC 1300 and NGC 1672 are examples of barred spiral galaxies. The Whirlpool galaxy and Messier 81 are examples of unbarred spiral galaxies.
The identifying characteristics of a spiral galaxy are disk-shaped rotating, spiral arms, and a bulge in the galactic core.  The spiral arms are where new hot stars are born.  "Bulge" in the galactic core has old stars.  This feature is common to the most spiral galaxies.

Elliptical galaxy
Elliptical galaxy 

An elliptical galaxy is a galaxy that has a ellipsoid (3D of ellipse) shape.  This type of galaxy are dominant in universe, especially in galaxy clusters.  The shape ranges from circle, ellipse, and cigar-shaped.  In Hubble Sequence, this shape can be represented as class :
 E0 (circle-shape)
 E53 (ellipse-shape)
 E7 (cigar-shaped)
Elliptical galaxies have a large range in size. The giant elliptical galaxy can be over a more 1 million light years and the smallest (know as "dwarf elliptical galaxy") are less than one-tenth the size of Milky Way The effective radius defines the area from which half its light comes. The mass of elliptical galaxy is also large. A giant elliptical galaxy can have mass of 1013 (many trillions) of solar masses.

Other kinds of galaxies
A lenticular galaxy is a galaxy seen as a disc shape.  The shape of a lenticular galaxy can be between spiral galaxy and elliptical galaxy.  The shape can be known by looking at the bulge of the galactic center.  If the bulge is very bright, it is a spiral galaxy

Related pages 
List of galaxies
List of nearest galaxies
Most distant things
Local Group
IC 1101: the largest known galaxy, with about 100 trillion stars.
Milky Way
Andromeda galaxy

References

Other websites 

 Galaxies, SEDS Messier pages
 An Atlas of The Universe
 Galaxies — Information and amateur observations
 The oldest galaxy yet found 
 Galaxies — discussed on BBC Radio 4's "In Our Time" programme
 Galaxy classification project, harnessing the power of the internet and the human brain
 How many galaxies are in our universe?
Geometry (from Ancient Greek: Γεωμετρία (romanized: Geometria (English: "Land measurement") derived from Γη (romanized: Ge; English: "Earth" or "land") and also derived from Μέτρον) (romanized: Métron; English: "A measure")) is a branch of mathematics that studies the size, shapes, positions and dimensions of things. We can only see shapes that are flat (2D) or solid (3D), but mathematicians (people who study math) are able to study shapes that are 4D, 5D, 6D, and so on.

Squares, circles and triangles are some of the simplest shapes in flat geometry. Cubes, cylinders, cones and spheres are simple shapes in solid geometry.

Uses 
Plane geometry can be used to measure the area and perimeter of a flat shape. Solid geometry can measure a solid shape's volume and surface area.
Geometry can be used to calculate the size and shape of many things. For example, geometry can help people find:
 the surface area of a house, so they can buy the right amount of paint
 the volume of a box, to see if it is big enough to hold a liter of food
 the area of a farm, so it can be divided into equal parts
 the distance around the edge of a pond, to know how much fencing to buy.

Origins 
Geometry is one of the oldest branches of mathematics. Geometry began as the art of surveying of land so that it could be shared fairly between people. The word "geometry" is from a Greek word that means "to measure the land". It has grown from this to become one of the most important parts of mathematics. The Greek mathematician Euclid wrote the first book about geometry, a book called The Elements.
Non-Euclidean geometry 
Plane and solid geometry, as described by Euclid in his textbook Elements, is called "Euclidean Geometry". This was simply called "geometry" for centuries. In the 19th century, mathematicians created several new kinds of geometry that changed the rules of Euclidean geometry. These and earlier kinds were called "non-Euclidean" (not created by Euclid). For example, hyperbolic geometry and elliptic geometry come from changing Euclid's parallel postulate.

Non-Euclidean geometry is more complicated than Euclidean geometry but has many uses. Spherical geometry for example is used in astronomy and cartography.
Examples 
Geometry starts with a few simple ideas that are thought to be true, called axioms. Such as:
 A point is shown on paper by touching it with a pencil or pen, without making any sideways movement. We know where the point is, but it has no size.
 A straight line is the shortest distance between two points. For example, Sophie pulls a piece of string from one point to another point. A straight line between the two points will follow the path of the tight string.
 A plane is a flat surface that does not stop in any direction. For example, imagine a wall that extends in all directions infinitely.

Related pages 
 Topology

References
Graph theory is a field of mathematics about graphs. A graph is an abstract representation of: a number of points that are connected by lines. Each point is usually called a vertex (more than one are called vertices), and the lines are called edges. Graphs are a tool for modelling relationships. They are used to find answers to a number of problems.
Some of these questions are:
 What is the best way for a mailman to get to all of the houses in the area in the least amount of time? The points could represent street corners and lines could represent the houses along the street. (see Chinese postman problem)
 A salesman has to visit different customers, but wants to keep the distance traveled as small as possible. The problem is to find a way so they can do it. This problem is known as Travelling Salesman Problem (and often abbreviated TSP). It is among the hardest problems to solve. If a commonly believed conjecture is true (described as P ≠ NP), then an exact solution requires one to try all possible routes to find which is shortest.
 How many colors would be needed to color a map, if countries sharing a border are colored differently? The points could represent the different areas and the lines could represent that two areas are neighboring. (look at the Four color theorem)
Can a sketch be drawn in one closed line? The lines of the drawing are the lines of the graph and when two or more lines collide, there is a point in the graph. The task is now to find a way through the graph using each line one time. (look at Seven Bridges of Königsberg)
Different kinds of graphs 

 Graph theory has many aspects. Graphs can be directed or undirected. An example of a directed graph would be the system of roads in a city. Some streets in the city are one way streets. This means, that on those parts there is only one direction to follow.
 Graphs can be weighted. An example would be a road network, with distances, or with tolls (for roads).
 The nodes (the circles in the schematic) of a graph are called vertices. The lines connecting the nodes are called edges. There can be no line between two nodes, there can be one line, or there can be multiple lines.
 In graph theory, Trees structures are widely used, they represent hierarchical structures. A Tree is a directed or undirected graph where there is no cycle, meaning: no way of going from one vertex (for example a town) to the same one using each edge you use only once (walking only once on each road you take).

History
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A visualization of the Seven Bridges of Königberg. Leonhard Euler solved this problem in 1736, which led to the development of topology, and modern graph theory.

A graph is an abstract data structure. It holds nodes that are usually related to each other. A node is a dataset, typically in the form of ordered pairs. Nodes are either connected or not connected to another node. The relation between nodes is usually defined as an Edge. Graphs are useful for their ability to associate nodes with other nodes.
There are a few representations of Graphs in practice.
Leonhard Euler used to live in a town called Königsberg. (Its name changed to Kaliningrad in 1946). The town is on the river Pregel. There is an island in the river. There are some bridges across the river. Euler wanted to walk around and use each of the bridges once. He asked if he could do this. In 1736, he published a scientific article where he showed that this was not possible. Today, this problem is known as the Seven Bridges of Königsberg. The article is seen as the first paper in the history of graph theory.

This article, as well as the one written by Vandermonde on the knight problem, carried on with the analysis situs initiated by Leibniz. Euler's formula was about the number of edges, vertices, and faces of a convex polyhedron was studied and generalized by Cauchy and L'Huillier, and is at the origin of topology.
The fusion of the ideas coming from mathematics with those coming from chemistry is at the origin of a part of the standard terminology of graph theory. In particular, the term "graph" was introduced by Sylvester in an article published in 1878 in Nature.

One of the most famous and productive problems of graph theory is the four color problem: "Is it true that any map drawn in the plane may have its regions colored with four colors, in such a way that any two regions having a common border have different colors?"

Graph theory in perspective 
Graph theory is an important part of mathematics and computer science. To many such problems, exact solutions do exist. Many times however, they are very hard to calculate. Therefore, very often, approximations are used. There are two kinds of such approximations, Monte-Carlo algorithms and Las-Vegas algorithms.

References

Related pages
Data structure
A goatee is a beard formed by a tuft of hair under the chin, resembling that of a billy goat.

Other websites 
Information on goatees 

Facial hair
Herm is the smallest of the Channel Islands that is open to the public.

Herm is only 1 miles long. Cars are banned from the small island just like its Channel Island neighbour, Sark. Unlike Sark, bicycles are banned too. The sandy white beaches make Herm a walker's paradise.

Population: 60 (2002).

Islands of the Channel Islands
History is the study of past events. People know what happened in the past by looking at things from the past including sources (like books, newspapers, scripts and letters), buildings and artifacts (like pottery, tools, coins and human or animal remains.) Libraries, archives, and museums collect and keep these things for people to study history. A person who studies history is called a historian. A person who studies pre-history and history through things left behind by ancient cultures is called an archaeologist. A person who studies mankind and society is called an anthropologist. The study of the sources and methods used to study and write history is called historiography.

People can learn about the past by talking to people who remember things that happened at some point in the past. This is called oral history. For example, when people who had been slaves and American Civil War survivors got old, some historians recorded them talking about their lives, so that history would not be lost.
In old times people in different parts of the world kept separate histories because they did not meet each other very often. Some groups of people never met each other. The rulers of Medieval Europe, Ancient Rome and Ancient China each thought that they ruled the only important parts of the world and that other parts were "barbarian". But they were still connected, even if they didn't realize it.

The term "historically" is used to say that something has been a certain way during most of its history. For example, a historically female university is a university which has had a student body that was mostly or entirely female for most of its history.  The term is often used for historically female and historically black (African American) schools.

Timeline of history
Pre-history
 Ancient history
 Sumer
 Ancient Egypt
 Babylonia
Ancient Armenia
 Ancient Greece
 Ancient India
 Ancient China and Japan, Korea, Mongolia
 Ancient Southeast Asia - Cambodia - Thailand - Indonesia
 Ancient North America - Iroquois, Mohawk, Huron, Haida, Lenape, Mohican, Cree, Sioux, Inuit, Dene
 Ancient Central America - Aztecs, Maya, Olmecs, Toltecs, Teotihuacan, Mixtecs
 Ancient South America - Inca, Chimu, Tihuanacu, Huari
 Ancient Africa
 Ancient Australia
 Roman Empire
 Christian Rome - Justinian to the rise of Byzantium
 Chinese Dynasties
 Byzantine Empire
 Early Islamic Caliphate - Muhammad to The Crusades
 Early Middle Ages - end of European Dark Ages to rise of Roman Catholic Church
 High Middle Ages and the Crusades - conflict with Islam, Cathars, pagan tribes in Lithuania, etc.
 Late Middle Ages - 13th century to 15th century
 Late Islamic Caliphate - to fall of Muslim Spain
 Mongol Empire
Mongol Empire
 Renaissance - 15th century renewal of science etc., based on texts from Ancient Greece and Roman Empire that were preserved by Muslims and captured by Christians
 European colonization of the Americas - 15th century impact on America
Spanish Empire
British Empire
 Baroque era - mid 16th century to mid-late 18th century
 Conflict of Ottoman Empire with Austria-Hungary
 Rise of the Qing Dynasty in China
 Enlightenment - mid 17th century to late 18th century
 19th century
British Empire
 20th century
History of Australia since colonizing Australia
History of the United States 
 Modern History and origins of modern world power structure
World War I
 World War II
 United Nations ascendance - how it became so central.
 Chinese Revolution, Partition of India, North Atlantic Treaty Organisation (NATO)
 US-Soviet Cold War including Korean War, Vietnam War, Soviet-Afghan War
 Recent conflicts in the Muslim World - Arab-Israeli Wars, US invasion of Afghanistan, US invasion of Iraq
Current events, modern economic history, modern social history and modern intellectual history take very different views of the way history has affected the way that we think today.

Related pages 

 List of historians
 World History
 Political economy
 Historical novel
Basic English 850 words

References