Aarushhh/wikipedia-simple-splitted huggingface dataset:
One reason for confusion about tree damage from construction involves the dormancy of trees during winter. Another factor is that trees may not show symptoms of damage until 24 months or longer after damage has occurred. For that reason, persons who do not know about caring for trees may not link the actual cause with the later damaged effect.

Various organizations have long recognized the importance of construction activities that may damage tree health. This can result in monetary losses due to tree damage and replacement costs. As a result, standard methods of tree management for building activities are well established and tested. 

 Developing a tree protection plan
 Developing a remediation plan (making damage good)
 Setting up tree protection zones (TPZs)
 Assessing tree damage, after building
 Doing the remediation plan

Trees in culture
Trees in culture 

The tree has always been a cultural symbol. Common icons are the World tree, for instance Yggdrasil, and the tree of life. The tree is often used to represent nature or the environment itself. A common mistake (wrong thing) is that trees get most of their mass from the ground. In fact, 99% of a tree's mass comes from the air.

Wishing trees 

A Wish Tree (or wishing tree) is a single tree, usually distinguished by species, position or appearance, which is used as an object of wishes and offerings. Such trees are identified as possessing a special religious or spiritual value. By tradition, believers make votive offerings in order to gain from that nature spirit, saint or goddess fulfillment of a wish.
Tree worship 
Tree worship refers to the tendency of many societies in all of history to worship or otherwise mythologize trees. Trees have played a very important role in many of the world's mythologies and religions, and have been given deep and sacred meanings throughout the ages. Human beings, seeing the growth and death of trees, the  elasticity of their branches, the sensitiveness and the annual (every year) decay and revival of their foliage, see them as powerful symbols of growth, decay and resurrection. The most ancient cross-cultural symbolic representation of the universe's construction is the 'world tree'.

World tree 

The tree, with its branches reaching up into the sky, and roots deep into the earth, can be seen to dwell in three worlds - a link between heaven, the earth, and the underworld, uniting above and below. It is also both a feminine symbol, bearing sustenance; and a masculine, phallic symbol - another union.
For this reason, many mythologies around the world have the concept of the World tree, a great tree that acts as an Axis mundi, holding up the cosmos, and providing a link between the heavens, earth and underworld. In European mythology the best known example is the tree Yggdrasil from Norse mythology.

The world tree is also an important part of Mesoamerican mythologies, where it represents the four cardinal directions (north, south, east, and west). The concept of the world tree is also closely linked to the motif of the Tree of life.

In literature 

In literature, a mythology was notably developed by J.R.R. Tolkien, his Two Trees of Valinor playing a central role in his  1964 Tree and Leaf. William Butler Yeats describes a "holy tree" in his poem The Two Trees (1893).

List of trees 
There are many types of trees. Here is a list of some of them:
Apple tree
 Coconut palm
 Cottonwood
 Eucalyptus (Gum tree)
 Fir 
 Horse chestnut
 Mangrove
 Maple
 Oak
 Palm
 Pine
 Redwood
 Rubber tree
 Willow
 Yew
 Birch
 Toona ciliata

Related pages 
 Wattezia is the earliest tree in the fossil record.

References

Other websites 

 Global Trees Campaign website
 Botanic Gardens Conservation International website

More reading
 
Basic English 850 words
In theatre, a tragedy as defined by Aristotle is a play that ends badly for the hero or heroine or others. A tragedy is usually about a person who has many good qualities, but also has one poor quality (called a "tragic flaw") that causes trouble for him, and maybe his family or friends.

Often in a tragedy, there is one possible event that the hero fears and tries to prevent, but no matter what he does, it makes this thing more and more sure to happen.  Tragedies originated in Ancient Greek theatre, where they were performed at religious festivals. The three most famous Greek tragedy writers were Aeschylus, Sophocles and Euripides. Later famous writers include Shakespeare and Jean Racine.

Sometimes the word tragedy is also used to mean something with a bad outcome in real life e.g. crime or death. It makes people cry when there’s sad scenes in movies .

Related pages
Catharsis
English Renaissance drama
Henrik Ibsen
Arthur Miller

Theatrical forms
Taxonomy is a branch of biology. It is about the laws and principles of classifying living things. From one type of taxonomy, many classifications might be produced.

Classification
The best-known kind of taxonomy is used for the classification of lifeforms (living and extinct). Each organism has a scientific name. This name is part of the biological classification of that species. The name is the same all over the world, so scientists from different places can understand each other. In addition, a species has a position in the tree of life. Thus the crow is Corvus corone, a member of the Corvidae family, and they are passerine birds. That is well agreed, but the classification of some groups is not agreed at present, and often several classifications are being discussed.
Living things are classified into three domains: bacteria, archaea and eukaryotes. The highest rank in a domain is the kingdom. Each kingdom has many smaller groups in it, called phyla. Each phylum has more smaller groups in it, called classes. This pattern looks like branches on a tree with smaller branches growing from them. Each species is put into a group because of what it does, how and what it eats, special body parts, and so on. At the end of the pattern, the groups (genera) are very small. Then each species in the genus is given its own name.

Binomial nomenclature 
When someone writes about a living thing and its formal scientific name, they write the genus and species name. This is known as binomial nomenclature, because it uses two names for each organism. The first is the genus name, and the second is the species in that genus. The scientific name of the domestic cat is Felis catus. Sometimes it is enough to write F. catus.
These are the major groups (ranks) used in taxonomy:
Kingdom --> Phylum --> Class --> Order --> Family --> Genus --> Species

Usage of Latin 
When people started naming species, Latin was a language widely used in Europe. All species names are still written in Latin. This has some advantages. Since Latin is no longer spoken, it is unchanging, and is owned by no-one. It gets over the problem of every language having its own names for animals and plants.

Scientists used to write the official description of each new species in Latin. On 1 January 2012, the International Botanical Congress changed to allow English (as well as Latin) for describing new plant species. The International Code of Zoological Nomenclature recommends choosing a language that is widely used, and that is used in the places where the species lives.
Cladism
An important modern approach to taxonomy is cladism. This approach is based on the branching (tree-like) course of evolution. Like traditional Linnaean classification, it uses traits to decide on the branches of the classification. It insists on groups being monophyletic. This has the effect that birds are not a class but a sub-group of dinosaurs. It also means the ranking system described above would be abolished.

So cladism has different principles of taxonomy, and produces a different kind of taxonomy. Decisions, where possible, are supported by DNA sequence analysis. Present-day biological classification is a mixture of the old Linnaean and the modern cladistic principles of taxonomy. In parts, it is changing rapidly. The classifications presented in Wikipedia at present are often a compromise between the two systems. The details are regularly discussed.
Turmoil in taxonomy
Today, there are many changes in the classification of living things. This turmoil in taxonomy has led to many alternative classifications. It is caused partly from the move from Linnaean to cladistic principles, and partly by the use of DNA sequence data in taxonomy. An example is: the way derived groups like birds should not be classified at the same level as the group they evolved from. Yet birds have traditionally been a class under the Linnaean system.

The turmoil sometimes results in differences between related pages. Pages may rely on different references and different authors' opinions as to the present best arrangement.

The following source is good on the differences between cladistic and taxonomic classification systems:
Grant, Verne 2003. Incongruence between cladistic and taxonomic systems. American Journal of Botany. 90 (9) 1263-1270.

Related pages
 Cladistics
 Molecular clock
 Molecular evolution
 Sequence analysis
 Biological classification
 Military taxonomy
References

Other websites
 Taxonomy Citizendium
The Sun is the star at the center of the Solar System.

The Sun may also mean:

Publications

United Kingdom 
 The Sun (United Kingdom), a current daily national tabloid
 The Sun (1792–1806), a defunct British newspaper 
 The Sun (1893–1906), a defunct British newspaper

United States 
 The Sun (magazine), a monthly literary and photography magazine
 The Sun (Lowell), a daily newspaper in Massachusetts
 The Sun (New York City), a defunct daily newspaper in New York (1833–1950)
 The New York Sun, 2002–2008
 The Sun (Sheridan), a defunct weekly newspaper in Oregon (1890–2014)
 Sun, later the Ann Arbor Sun, a defunct underground newspaper in Michigan
 The Sun, later called Peck's Sun, a Wisconsin newspaper founded by George Wilbur Peck
 The U.S. Sun, the U.S. online edition of The Sun (United Kingdom)
Elsewhere 
Sun Newspapers (Northern Territory), community newspapers in Darwin, Australia
The Sun (Hong Kong), a defunct Chinese-language newspaper (1999–2016)
 The SUN (Hong Kong), an English-language newspaper for Filipinos
 The Sun (Malaysia), a daily Malaysian tabloid
 The Sun (New Zealand), a defunct New Zealand newspaper
 The Sun (Nigeria), a daily Nigerian newspaper
 The Sun (Rangoon), a defunct Burmese newspaper (1911–1954)
 The Sun (Sydney), a defunct Australian tabloid (1910–1988)

Arts and entertainment

Movies 
 The Sun (movie), a 2005 Russian biographical movie

Music

Artists 
 The Sun (American band)
 The Sun (Estonian band)
 The Sun (Italian band), previously under the name Sun Eats Hours

Albums 
 The Sun (Cat Empire album)
 The Sun (Fridge album)
 The Sun, an album by FanFan

Songs 
 "The Sun", by Maroon 5 from the 2002 album Songs About Jane
 "The Sun", a 2014 single by Parov Stelar
 "The Sun", an original Barney song from Barney in Outer Space
Fictional and literary uses 
 The Sun (Tarot card), a trump card in the tarot deck
 The Sun (wordless novel), a 1919 book of woodcut prints by Frans Masereel
 Ash-Shams ("The Sun"), the ninety-first sura of the Qur'an
 The Sun, a The House of the Dead III character

Other 
 The Sun (St. Paul's Churchyard), a historical bookseller in London

Related pages 
 Sun (disambiguation)
 Sun (newspaper)
 The Sunday Sun (disambiguation), name of various newspapers
 Le Soleil (French for "The Sun"), name of various newspapers
 Die Son (Afrikaans for "The Sun"), a daily South African tabloid
A temple is a building where people go to practice their religion. In a temple people may perform religious rituals, ceremonies, and pray. Thus, a temple is a general term for a house of worship. Christians usually call their religious buildings churches.

Some examples of temples from different religions:
Hinduism (Mandir)
Buddhism (Shaolin)
Temples at Uppsala
Greek temple
Temple in Jerusalem
Mormon temple
Roman temple
Reform Judaism's synagogues.
Baha'i (Mashriqu'l-Adhkar)
Temples in Bangkok

Other websites
Theft is when one person or group takes from another person, business, or state any object, money, or information without permission and does not intend to return it. A person who has been convicted of theft may be called a thief. However, the practice of engaging in theft is also called stealing. There are many different types of theft, such as pickpocketing and shoplifting. Burglary and robbery are separate crimes which involve theft.

Stealing is basic and is illegal almost everywhere.  Thieves steal things sometimes because they want to have something for themselves, or because they want to sell something for money.  Sometimes thieves will make plans to rob a store, bank, house, or person, and sometimes they will just see a chance to steal something and take it.  Some thieves have kleptomania.
The United Kingdom of Great Britain and Northern Ireland, often shortened to the United Kingdom (or UK), or just Britain, is a sovereign country in Western Europe. It is a constitutional monarchy of four countries which were once separate: England, Wales, Scotland and Northern Ireland.

It is part of the United Nations, the Commonwealth of Nations, NATO, the G7, and formerly the European Union. It had the sixth largest economy in the world by nominal GDP in 2019.

About 95 percent of the UK's population are English speakers. 5.5 per cent of the population speak languages brought to the UK as a result of relatively recent immigration.

The UK has many cities. London is the biggest city in the UK and is the nation's capital city. There are also other large cities in England such as Birmingham, Manchester, Liverpool, Leeds, Bristol and Newcastle upon Tyne. Scotland has the big cities of Edinburgh and Glasgow. Cardiff and Swansea are in Wales and Derry and Belfast are in Northern Ireland.
Between the 17th and mid 20th-centuries, Britain became a world power. It became a colonial empire that controlled large areas of Africa, Asia, North America and Oceania. 

At its height in 1922, more than 458 million people lived in the British Empire, one-fifth of the Earth's population. Its area was 13,012,000 square miles: almost a quarter of the Earth's land area. The Empire was sometimes called 'the Empire on which the Sun never sets', meaning it is always daytime someplace in the Empire. Many countries left and became independent from the Empire in the 20th century, although Britain keeps links with most countries of its former empire and also still controls fourteen colonies.

History

Prehistory 

Humans have lived in Britain for almost a million years. They did not live there all the time, probably because the climate was too extreme at times.
Archaeological remains show that the first group of modern people to live in the British Isles were hunter-gatherers after the last ice age ended. The date is not known: perhaps as early as 8000BC but certainly by 5000BC. They built mesolithic wood and stone monuments. Stonehenge was built between 3000 and 1600BC. Celtic tribes arrived from mainland Europe. Britain was a changing collection of tribal areas, with no overall leader. Julius Caesar tried to invade (take over) the island in 55BC but was not able to do so. The Romans successfully invaded in 43AD.
Written history began in Britain when writing was brought to Britain by the Romans. Rome ruled in Britain from 44AD to 410AD. They ruled the southern two-thirds of Great Britain. The Romans never took over Ireland and never fully controlled Scotland, the land north of the valleys of the River Forth and River Clyde. Their northern border varied from time to time and was marked sometimes at Hadrian's Wall (in modern England), sometimes at the Antonine Wall (in modern Scotland).

After the Romans, waves of immigrants came to Britain. Some were German tribes: the Angles, Saxons and Jutes. Others were Celts, like the Scoti, who came to Great Britain from Ireland. English and Scots are Germanic languages. They developed from Old English. This was spoken by the Anglo-Saxons in an area from the River Forth to the River Tamar.
Middle Ages 
A later wave of immigration was that of the Vikings, during the Early Middle Ages or Viking Age. During the Viking invasion of Britain, they set up their own kingdom in north-western England, which the Anglo-Saxons named the "Danelaw", after the Danes who lived there and controlled the land. Vikings from Scandinavia also controlled most of the islands which are now part of Scotland, including the Outer Hebrides, the Inner Hebrides, and the Northern Isles (the Shetland Islands and the Orkney Islands). 

 

After a long period when Anglo-Saxon England was split into various kingdoms, it was made into one kingdom by Æthelstan (Athelstan) in 945 AD. In the 13th century, the lands of Wales were unified by force with England by the wars of Edward I of England ("Edward Longshanks").

Early modern history
Union of the Crowns 
There were hundreds of years of fighting between both kingdoms of Great Britain. In 1603, when Queen Elizabeth I of England died, her closest relative was King James VI of Scotland. He became king of England and Ireland as well as the king of Scotland. The kingdoms of England, Ireland, and Scotland had the same monarch ever since. James VI and I was the first to be named "King of Great Britain", and he ordered the design of the Union Jack. The Union Jack has been the British national flag ever since.
Union of 1707 
In 1707, the Parliaments of England and Scotland agreed on the Treaty of Union, which joined the two countries into one country called the United Kingdom of Great Britain under Queen Anne with the Acts of Union 1707. This union merged Scotland and England into one kingdom. England and Scotland kept their own laws, with English law in England and Wales and Scots law in Scotland. The division between the Church of Scotland and the Church of England continued. Ireland and Great Britain continued to have the same king, but Ireland did not become part of the new kingdom in 1707.

Modern history
Modern history

Union of 1801 
Scotland and England had already independently had much influence over Ireland since 1200. In 1800 laws were passed in the parliaments of Great Britain and Ireland to merge the two kingdoms and their two parliaments. The country was then called the United Kingdom of Great Britain and Ireland. The Union Jack was changed so that the flag of Saint Patrick (a red saltire) shows Ireland to be a part of the country.

In 1922 much of Ireland became independent from the United Kingdom as the Irish Free State (now called Ireland). However, six northern counties (called Northern Ireland) are part of the United Kingdom. The country was renamed the United Kingdom of Great Britain and Northern Ireland in 1927.
The new Parliament of Northern Ireland set up in the 1920s stopped working in the 1970s, because of The Troubles. However, devolution started again with the Northern Ireland Assembly after the Belfast Agreement (the "Good Friday Agreement") in 1998. Devolution in Scotland and Wales started the Scottish Parliament and the Welsh Parliament the same year.

The United Kingdom was a member state of the European Union (EU) and an older organization, the European Economic Community (EEC), from 1973 until Brexit in 2020.

Geography 

The UK is northwest off the coast of mainland Europe. Around the UK are the North Sea, the English Channel and the Atlantic Ocean. The UK also rules, usually indirectly, a number of smaller places (mostly islands) around the world, which are known as British Overseas Territories. They were once part of the British Empire. Examples are Gibraltar (on the Iberian Peninsula next to the Strait of Gibraltar) and the Falkland Islands (in the south Atlantic Ocean).
The weather of the United Kingdom is changeable and unpredictable. Summers are moderately warm, winters are cool to cold. Rain falls throughout the year, and more on the west than the east because of its northerly latitude and the warm water from the Atlantic Ocean's Gulf Stream. The usually moderate prevailing winds from the Atlantic may be interrupted by Arctic air from the northeast or hot air from the Sahara.

The United Kingdom is reducing greenhouse gas emissions. It has met some Kyoto Protocol targets. It has signed the Paris Agreement. The British government want the UK to be carbon neutral by the year 2050.

Climate 
The United Kingdom has an oceanic climate.

The highest temperature ever recorded in the United Kingdom was , on 19 July 2022 in Coningsby. The lowest temperature ever recorded was , on February 11, 1895 & January 10, 1982 in Braemar, and December 30, 1995 in Altnaharra.

Politics
Politics

The United Kingdom is a parliamentary democracy based on a constitutional monarchy. The people of the United Kingdom vote for a members of Parliament to speak for them and to make laws for them. King Charles III is the King of the United Kingdom of Great Britain and Northern Ireland and is the head of state. The government, led by the Prime Minister, governs the country and appoints cabinet ministers. Today, the Prime Minister is Rishi Sunak, who is the leader of the centre-right Conservative Party.

Parliament is where laws are made. It has three parts: the House of Commons, the House of Lords, and the King. The House of Commons is the most powerful part. It is where Members of Parliament sit.
Scotland has its own devolved Parliament with the power to make laws on things like education, health and Scottish law. Northern Ireland and Wales have their own devolved legislatures which have some powers but less than the Scottish parliament. The Parliament of the United Kingdom is sovereign and it could end the devolved administrations at any time. The UK is a unitary state and not a federation of states.

Parliament

The Parliament of the United Kingdom is the legislature, the political assembly that makes laws and decides tax. The British people are represented by members of parliament (MPs) in the House of Commons of the United Kingdom. MPs are chosen in elections. The MPs in the House of Commons decide who will be the Prime Minister of the United Kingdom. The prime minister decides who will be in the British Government (His Majesty's Government). The government is not controlled by the king or queen, but by Parliament. In Britain, Parliament is made up of the House of Commons and the House of Lords.
Almost all members of Parliament belong to political parties. The biggest parties are the Conservative Party, Labour Party, the Scottish National Party and the Liberal Democrats. Members of the same party agree to work together. A party (often with more than half the seats: a majority) forms the government. The leader of the party becomes the prime minister, who then chooses the other ministers. Because the government has a majority in Parliament, it can normally control what laws are passed.

The British Parliament is in Westminster, in London. It has power over the whole of the United Kingdom. Wales, Scotland and Northern Ireland each have their own parliaments as well, and these have more limited powers. England does not have a separate parliament.
Scotland has the Scottish Parliament at Holyrood in Edinburgh. Wales has the Welsh Parliament in Cardiff. Northern Ireland has the Northern Ireland Assembly at Stormont in Belfast. There are also parliaments in the Isle of Man and in Jersey and Guernsey (the Channel Islands), which are all island states for which the UK has responsibility in international law. Man, Jersey, and Guernsey are "crown dependencies". Some British Overseas Territories have their own legislatures.

Parts of the UK
Countries (nations) 
About 68 million people live in the UK (2022). They can be divided into four big nationalities based on the countries where they live (or where they were born or their ancestry). Each country has a demonym for its people (for example; England's people are English), but no matter which country someone is from, they have a British nationality.
  is the biggest country, where most people in the UK live. People who live in England are called English. Their native language is called English, which is spoken by most people in England. England's land is split between regions. 
 , north of England, is the second biggest country. People who live there are called Scottish, and a Scottish person may be called a Scot. Some speak a language other than English: Scottish Gaelic, a Gaelic language. Scottish English, on the other hand, is a version of English.
is to the west of England. Its people are called Welsh and they have their own Celtic language which is also called Welsh. Not everyone in Wales can speak Welsh, but almost everyone can speak English.
  is the smallest country. Unlike the other three countries, it is not on the island of Great Britain: it is part of the island called Ireland. Northern Ireland takes up about a sixth of Ireland (with the Republic of Ireland taking up the remainder). People who live in Northern Ireland are either Irish, British, or Northern Irish. The people who live here speak English.
Crown dependencies 

The crown dependencies are three nations which are not part of any of the four countries in the UK. They are: the Isle of Man, Jersey and Guernsey. Unlike the four countries, the governments of the crown dependencies have almost full power over the dependencies, with the exception of military and international relations. Everybody from a crown dependency has a British nationality.

Overseas Territories 

The British Overseas Territories are former colonies of the British Empire which have not become independent from the UK. There are fourteen. Some have civilisations on them while others are military bases. Most of them have their own governments. The UK is responsible for their defence and international relationships. Everybody from an overseas territory has a British nationality.
Military
The United Kingdom has one of the most advanced militaries in the world, alongside such countries such as the USA and France, and operates a large navy (Royal Navy), a sizable army, (British Army) and an air force (Royal Air Force).

From the 18th century to the early 20th century, the United Kingdom was one of the most powerful nations in the world, with a large and powerful navy (due to the fact it was surrounded by sea, so a large navy was the most practical option). This status has faded in recent times, but it remains a member of various military groups such as the UN Security Council and NATO. It is also still seen as a great military power.

Economy

The United Kingdom is a developed country with the sixth-largest economy in the world. It was a superpower during the 18th, 19th and early 20th century and was considered since the early 1800s to be the most powerful and influential nation in the world, in politics, economics and in military strength.
Literature
William Shakespeare was an English playwright. He wrote plays in the late 16th century. Some of his plays were Romeo and Juliet and Macbeth. In the 19th century, Jane Austen and Charles Dickens were novelists. Twentieth-century writers include the science-fiction novelist H. G. Wells and J. R. R. Tolkien. The children's fantasy Harry Potter series was written by J. K. Rowling. Aldous Huxley was also from the United Kingdom.

English language literature is written by authors from many countries. Eight people from the United Kingdom have won the Nobel Prize in Literature. Seamus Heaney is a writer who was born in Northern Ireland.

Arthur Conan Doyle from Scotland wrote the Sherlock Holmes detective novels. He was from Edinburgh. The poet Dylan Thomas brought Welsh culture to international attention.
Education
The nature of education is a devolved matter in Scotland, Wales and Northern Ireland. They, and England, have separate, but similar, systems of education. They all have laws that a broad education is required from ages five to eighteen, except for in Scotland where school departure is allowed from the age of sixteen. Pupils attend state funded schools (academy schools, faith schools, grammar schools, city technology colleges, studio schools) and other children attend independent fee-paying schools (known as public schools.

There have been universities in Britain since the Middle Ages. The "ancient universities" started at this time and in the Renaissance. They are: the University of Oxford, the University of Cambridge, the University of St Andrews, the University of Glasgow, the University of Aberdeen, and the University of Edinburgh. These are the oldest universities in the English-speaking world.
The University of Cambridge, the University of Oxford, and London universities (University College London, the London School of Economics, King's College London and Imperial College London) collectively form the Golden Triangle of universities in the south-east of England. A broader group of twenty universities form the Russell Group of research universities.

Media 
The BBC is an organisation in the United Kingdom. It broadcasts in the United Kingdom and other countries on television, radio and the Internet. The BBC also sells its programs to other broadcasting companies around the world. The organisation is run by a group of twelve governors who have been given the job by the Queen, on the advice of government ministers.
Transport 
Road traffic in the United Kingdom drives on the left-hand side of the road (unlike the Americas and most of Europe), and the driver steers from the right-hand side of the vehicle. The road network on the island of Great Britain is extensive, with most local and rural roads having evolved from Roman and Medieval times. Major routes developed in the mid 20th Century were made to the needs of the motor car. The multi-lane high speed motorway (freeway) network was mostly built in the 1960s and 1970s. It links major towns and cities.

The system of rail transport was invented in England and Wales, so the United Kingdom has the oldest railway network in the world. It was built mostly during the Victorian era. At the heart of the network are five long-distance main lines which radiate from London to the major cities and secondary population centres with dense commuter networks in the regions. The newest part of the network connects London to the Channel Tunnel from St Pancras station.
The British Rail network is partly privatized, with privately owned train operating companies providing service along particular lines or regions. The tracks, signals, and stations are owned by a Government controlled company called Network Rail. In Northern Ireland, the NI Railways is the national railway. The system of underground railways in London, known as the Tube, has been copied by many other cities.

Most domestic air travel in the United Kingdom is between London and the major cities in Scotland and the North of England and Belfast. London-Heathrow is the nation’s largest airport and is one of the most important international hubs in the world. Other major airports with principal international service include London-Gatwick, Birmingham, Manchester and Glasgow. An extensive system of ferry networks operates. The Isle of Man and the Channel Islands also have domestic passenger and freight routs.

Languages
Languages

Major languages spoken in the United Kingdom other than English include Polish (500,000 approximate number of speakers in the United Kingdom), Eastern Panjabi or Punjabi (471,000), Bengali (400,000), Urdu (400,000), Cantonese (300,000), Greek (200,000), Southwestern Caribbean Creole English (170,000).

Native languages include:

Celtic languages

Brittonic or Bythonic languages
 Welsh
 Cornish

Goidelic or Gaelic languages
 Irish Gaelic
 Scottish Gaelic
 Manx language

Germanic languages
 English
 Scots
 Ulster Scots

Notes

References

Other websites

 
Commonwealth realms
Current monarchies
English-speaking countries
G8 nations
G7 nations
The universe is all of time and space and its contents. It is made of many millions of billions of stars and planets and enormous clouds of gas separated by a big space. The Big Bang created the universe. 

Astronomers can use telescopes to look at very distant galaxies. This is how they see what the universe looked like a long time ago. This is because the light from distant parts of the Universe takes a very long time to reach us. From these observations, it seems the physical laws and constants of the Universe have not changed.

Physicists are currently unsure if anything existed before the Big Bang. They are also unsure whether the size of the Universe is infinite, meaning its size never ends as it has been expanding since the Big Bang.

History 

People have long had ideas to explain the Universe. Most early ideas had the Earth at the centre of the Universe. This is known as geocentrism.
Some ancient Greeks thought that the Universe has infinite space and has existed forever. They thought it had a set of celestial spheres which corresponded to the fixed stars, the Sun and various planets. The spheres circled about a round but unmoving Earth.

Over hundreds of years, better observations led to Copernicus's Sun-centred model, known as heliocentrism. This was very controversial at the time, and was fought by religious authorities, most famously by the Christian church (see Giordano Bruno and Galileo).

The invention of the telescope in the Netherlands, 1608, was a very important moment in astronomy. By the middle of the 1800s, telescopes were good enough for other galaxies to be seen. The modern optical (uses visible light) telescope is still more advanced. Meanwhile, Isaac Newton improved the ideas of gravity and dynamics (equations) and showed how the Solar System worked.
In the 1900s, even better telescopes showed astronomers that the Solar System is in a galaxy made of billions of stars, which we call the Milky Way. Other galaxies exist outside it, as far as we can see. This started a new kind of astronomy called cosmology, in which astronomers study what these galaxies are made of and how they are spread out through so they can learn more about the history of the Universe and how it works. By measuring the redshift of galaxies, cosmologists soon discovered that the Universe is expanding (see: Hubble).
Big Bang 
The most used scientific model of the Universe is known as the Big Bang theory, which says the Universe expanded from a single point that held all the matter and energy of the Universe. There are many kinds of scientific evidence that support the Big Bang idea. Astronomers think that the Big Bang happened about 13.73 billion years ago, making the Universe 13.73 billion years old. Since then, the universe has expanded to be at least 93 billion light years, or 8.80  metres, in diameter. It is still expanding right now, and the expansion is getting faster.
However, astronomers are still not sure what is causing the universe to expand. Because of this, astronomers call the mysterious energy causing the expansion dark energy. By studying the expansion of the Universe, astronomers have also realized most of the matter in the Universe may be in a form which cannot be observed by any scientific equipment we have. This matter has been named dark matter. Just to be clear, dark matter and energy have not been observed directly (that is why they are called 'dark'). However, many astronomers think they must exist, because many astronomical observations would be hard to explain if they didn't.

Some parts of the universe are expanding even faster than the speed of light. This means the light will never be able to reach us here on Earth, so we will never be able to see these parts of the universe. We call the part of the universe we can see the observable universe.
Myths
The word Universe comes from the Old French word Univers, which comes from the Latin word universum. The Latin word was used by Cicero and later Latin authors in many of the same senses as the modern English word is used.

A different interpretation (way to interpret) of unvorsum is "everything rotated as one" or "everything rotated by one". This refers to an early Greek model of the Universe. In that model, all matter was in rotating spheres centered on the Earth; according to Aristotle, the rotation of the outermost sphere was responsible for the motion and change of everything within. It was natural for the Greeks to assume that the Earth was stationary and that the heavens rotated about the Earth, because careful astronomical and physical measurements (such as the Foucault pendulum) are required to prove otherwise.

The most common term for "Universe" among the ancient Greek philosophers from Pythagoras onwards was το παν (The All), defined as all matter (το ολον) and all space (το κενον).
Broadest meaning 
The broadest word meaning of the Universe is found in De divisione naturae by the medieval philosopher Johannes Scotus Eriugena, who defined it as simply everything: everything that exists and everything that does not exist.

Time is not considered in Eriugena's definition; so, his definition includes everything that exists, has existed and will exist, as well as everything that does not exist, has never existed and will never exist. This all-embracing definition was not adopted by most later philosophers, but something similar is in quantum physics.

Definition as reality 

Usually the Universe is thought to be everything that exists, has existed, and will exist. This definition says that the Universe is made of two elements: space and time, together known as space-time or the vacuum; and matter and different forms of energy and momentum occupying space-time. The two kinds of elements behave according to physical laws, in which we describe how the elements interact.
A similar definition of the term universe is everything that exists at a single moment of time, such as the present or the beginning of time, as in the sentence "The Universe was of size 0".

In Aristotle's book The Physics, Aristotle divided το παν (everything) into three roughly analogous elements: matter (the stuff of which the Universe is made), form (the arrangement of that matter in space) and change (how matter is created, destroyed or altered in its properties, and similarly, how form is altered). Physical laws were the rules governing the properties of matter, form and their changes. Later philosophers such as Lucretius, Averroes, Avicenna and Baruch Spinoza altered or refined these divisions. For example, Averroes and Spinoza have active principles governing the Universe which act on passive elements.
Space-time definitions 
It is possible to form space-times, each existing but not able to touch, move, or change (interact with each other. An easy way to think of this is a group of separate soap bubbles, in which people living on one soap bubble cannot interact with those on other soap bubbles. According to one common terminology, each "soap bubble" of space-time is denoted as a universe, whereas our particular space-time is denoted as the Universe, just as we call our moon the Moon. The entire collection of these separate space-times is denoted as the multiverse. In principle, the other unconnected universes may have different dimensionalities and topologies of space-time, different forms of matter and energy, and different physical laws and physical constants, although such possibilities are speculations.

Observable reality 
According to a still-more-restrictive definition, the Universe is everything within our connected space-time that could have a chance to interact with us and vice versa.
According to the general idea of relativity, some regions of space may never interact with ours even in the lifetime of the Universe, due to the finite speed of light and the ongoing expansion of space. For example, radio messages sent from Earth may never reach some regions of space, even if the Universe would exist forever; space may expand faster than light can traverse it.

It is worth emphasizing that those distant regions of space are taken to exist and be part of reality as much as we are; yet we can never interact with them, even in principle. The spatial region within which we can affect and be affected is denoted as the observable universe.
Strictly speaking, the observable Universe depends on the location of the observer. By travelling, an observer can come into contact with a greater region of space-time than an observer who remains still, so that the observable Universe for the former is larger than for the latter. Nevertheless, even the most rapid traveler may not be able to interact with all of space. Typically, the 'observable Universe' means the Universe seen from our vantage point in the Milky Way Galaxy.

Basic data on the Universe
The Universe is huge. The matter which can be seen is spread over a space at least 93 billion light years across. For comparison, the diameter of a typical galaxy is only 30,000 light-years, and the typical distance between two neighboring galaxies is only 3 million light-years. As an example, our Milky Way Galaxy is roughly 100,000 light years in diameter, and our nearest sister galaxy, the Andromeda Galaxy, is located roughly 2.5 million light years away. 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).
Typical galaxies range from dwarf galaxies with as few as ten million (107) stars up to giants with one trillion (1012) stars, all orbiting the galaxy's center of mass. Thus, a very rough estimate from these numbers would suggest there are around one sextillion (1021) stars in the observable Universe; though a 2003 study by Australian National University astronomers resulted in a figure of 70 sextillion (7 x 1022).

The matter that can be seen is spread throughout the Universe when averaged over distances longer than 300 million light-years. However, on smaller length-scales, matter is observed to form 'clumps', many atoms are condensed into stars, most stars into galaxies, most galaxies into galaxy groups and clusters and, lastly, the largest-scale structures such as the Great Wall of galaxies.
The present overall density of the Universe is very low, roughly 9.9 × 10−30 grams per cubic centimetre. This mass-energy appears to consist of 73% dark energy, 23% cold dark matter and 4% ordinary matter. The density of atoms is about a single hydrogen atom for every four cubic meters of volume. The properties of dark energy and dark matter are not known. Dark matter slows the expansion of the Universe. Dark energy makes its expansion faster.

The Universe is old, and changing. The best good guess of the Universe's age is 13.798±0.037 billion years old, based on what was seen of the cosmic microwave background radiation. Independent estimates (based on measurements such as radioactive dating) agree, although they are less precise, ranging from 11 to 20 billion years.
to 13–15 billion years.
The relative amounts of different chemical elements — especially the lightest atoms such as hydrogen, deuterium and helium — seem to be identical in all of the Universe and throughout all of the history of it that we know of. The Universe seems to have much more matter than antimatter. The Universe appears to have no net electric charge. Gravity is the dominant interaction at cosmological distances. The Universe also seems to have no net momentum or angular momentum. The absence of net charge and momentum is expected if the Universe is finite.

The Universe appears to have a smooth space-time continuum made of three spatial dimensions and one temporal (time) dimension. On the average, space is very nearly flat (close to zero curvature), meaning that Euclidean geometry is experimentally true with high accuracy throughout most of the Universe. However, the Universe may have more dimensions, and its spacetime may have a multiply connected global topology.
The Universe has the same physical laws and physical constants throughout. According to the prevailing Standard Model of physics, all matter is composed of three generations of leptons and quarks, both of which are fermions. These elementary particles interact via at most three fundamental interactions: the electroweak interaction which includes electromagnetism and the weak nuclear force; the strong nuclear force described by quantum chromodynamics; and gravity, which is best described at present by general relativity.

Special relativity holds in all the Universe in local space and time. Otherwise, general relativity holds. There is no explanation for the particular values that physical constants appear to have throughout our Universe, such as Planck's constant h or the gravitational constant G. Several conservation laws have been identified, such as the conservation of charge, conservation of momentum, conservation of angular momentum and conservation of energy.

Theoretical models
Theoretical models

General theory of relativity 

Accurate predictions of the Universe's past and future require an accurate theory of gravitation. The best theory available is Albert Einstein's general theory of relativity, which has passed all experimental tests so far. However, since rigorous experiments have not been carried out on cosmological length scales, general relativity could conceivably be inaccurate. Nevertheless, its predictions appear to be consistent with observations, so there is no reason to adopt another theory.
Einstein's field equations include a cosmological constant (Lamda: Λ), that is related to an energy density of empty space. Depending on its sign, the cosmological constant can either slow (negative Λ) or accelerate (positive Λ) the expansion of the Universe. Although many scientists, including Einstein, had speculated that Λ was zero, recent astronomical observations of type Ia supernovae have detected a large amount of dark energy that is accelerating the Universe's expansion. Preliminary studies suggest that this dark energy is related to a positive Λ, although alternative theories cannot be ruled out as yet.

Big Bang model
Big Bang model 

The prevailing Big Bang model accounts for many of the experimental observations described above, such as the correlation of distance and redshift of galaxies, the universal ratio of hydrogen:helium atoms, and the ubiquitous, isotropic microwave radiation background. As noted above, the redshift arises from the metric expansion of space; as the space itself expands, the wavelength of a photon traveling through space likewise increases, decreasing its energy. The longer a photon has been traveling, the more expansion it has undergone; hence, older photons from more distant galaxies are the most red-shifted. Determining the correlation between distance and redshift is an important problem in experimental physical cosmology.
Other experimental observations can be explained by combining the overall expansion of space with nuclear physics and atomic physics. As the Universe expands, the energy density of the electromagnetic radiation decreases more quickly than does that of matter, since the energy of a photon decreases with its wavelength. Thus, although the energy density of the Universe is now dominated by matter, it was once dominated by radiation; poetically speaking, all was light. As the Universe expanded, its energy density decreased and it became cooler; as it did so, the elementary particles of matter could associate stably into ever larger combinations. Thus, in the early part of the matter-dominated era, stable protons and neutrons formed, which then associated into atomic nuclei. At this stage, the matter in the Universe was mainly a hot, dense plasma of negative electrons, neutral neutrinos and positive nuclei
. Nuclear reactions among the nuclei led to the present abundances of the lighter nuclei, particularly hydrogen, deuterium, and helium. Eventually, the electrons and nuclei combined to form stable atoms, which are transparent to most wavelengths of radiation; at this point, the radiation decoupled from the matter, forming the ubiquitous, isotropic background of microwave radiation observed today.