the-french-artist/wikipedia_20220301.simple_sentence_split huggingface dataset:
Tree climbing is an "on rope" activity that puts together many different tricks and gear originally derived from rock climbing and caving.
These techniques are used to climb trees for many purposes, including tree care (arborists), animal rescue, recreation, sport, research, and activism.
The three big sources of tree damage are biotic (from living sources), abiotic (from non-living sources) and deforestation (cutting trees down).
Biotic sources would include insects which might bore into the tree, deer which might rub bark off the trunk, or fungi, which might attach themselves to the tree.
Abiotic sources include lightning, vehicles impacts, and construction activities.
Construction activities can involve a number of damage sources, including grade changes that prevent aeration to roots, spills involving toxic chemicals such as cement or petroleum products, or severing of branches or roots.
People can damage trees also.
Both damage sources can result in trees becoming dangerous, and the term "hazard trees" is commonly used by arborists, and industry groups such as power line operators.
Hazard trees are trees which due to disease or other factors are more susceptible to falling during windstorms, or having parts of the tree fall.
Trees are similar to people.
Both can take a lot of some types of damage and survive, but even small amounts of certain types of trauma can result in death.
Arborists are very aware that established trees will not tolerate any appreciable disturbance of the root system.
Even though that is true, most people and construction professionals do not realize how easily a tree can be killed.
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
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'.
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, 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:
Wattezia is the earliest tree in the fossil record.
Global Trees Campaign website
Botanic Gardens Conservation International website
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.
Theatrical forms
Taxonomy is a branch of science.
It is about the laws and principles of classifying things.
From one type of taxonomy, many classifications might be produced.
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.
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.
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.
Grant, Verne 2003.
Incongruence between cladistic and taxonomic systems.
American Journal of Botany.
90 (9) 1263-1270.
Taxonomy Citizendium
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
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)
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
The Sun (movie), a 2005 Russian biographical movie
The Sun (American band)
The Sun (Estonian band)
The Sun (Italian band), previously under the name Sun Eats Hours
The Sun (Cat Empire album)
The Sun (Fridge album)
The Sun, an album by FanFan
"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
The Sun (St. Paul's Churchyard), a historical bookseller in London
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.
Hinduism (Mandir)
Buddhism (Shaolin)
Temples at Uppsala
Greek temple
Mormon temple
Reform Judaism's synagogues.
Baha'i (Mashriqu'l-Adhkar)
Temples in Bangkok
Theft is when one person or group takes from another persons or state any object, money, or information without permission.
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.
When thieves steal things for money, they usually pick cars, electronics, laptops, or other things they can sell easily.
Sometimes thieves use pawn shops to sell things easily to someone who will not ask questions.
The United Kingdom of Great Britain and Northern Ireland or simply the United Kingdom (UK) is a sovereign country in Western Europe.
It is a constitutional monarchy that is made up of four separate countries: England, Wales, Scotland and Northern Ireland.
It is a member of the United Nations, the Commonwealth, NATO, the G8, and formerly the EU.
It had the sixth largest economy in the world by nominal GDP in 2019.
Around 66 million people live in the UK (2018).
They can be divided into four big nationalities based on the countries where they live (or where they were born or their ancestry).
England 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.
Scotland, north of England, is the second biggest country.
People who live there are called Scottish, and a Scottish person may be called a Scottish.
Some speak a language other than English: Scottish Gaelic, a Gaelic language.
Scottish English, on the other hand, is a version of English.
Wales 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.
Northern Ireland 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 usually speak English.
About 95 per cent 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 big cities in England including 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 is in Northern Ireland.
Between the 17th and mid 20th-centuries, Britain was 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 the sun is always shining on at least one of its territories.
Almost all countries left and became independent from the empire in the 20th century, although Britain keeps links with most countries of its former empire.
The "UK" is a common abbreviation of United Kingdom, which derives from when its Kingdom had been United.
Species of humans have lived in Britain, for almost a million years.
The occupation was not continuous, probably because the climate was too extreme at times for people to live there.
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 Caledonia, 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, the language spoken by the Anglo-Saxons of Anglo-Saxon England, an area stretching from the River Forth to the River Tamar.
A later wave of immigration was that of the Vikings, during the Early Middle Ages' 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 945AD.
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.
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.
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).
In the British Isles, the UK is made up of four different countries: Wales, England and Scotland and Northern Ireland.
The capital city of Wales is Cardiff.
The capital city of England is London.
The capital city of Scotland is Edinburgh and the capital city of Northern Ireland is Belfast.
Other large cities in the UK are Birmingham, Bristol, Manchester, Liverpool, Newcastle upon Tyne, Leeds, Sheffield, Glasgow, Southampton, Leicester, Coventry, Bradford and Nottingham.
The physical geography of the UK varies greatly.
England consists of mostly lowland terrain, with upland or mountainous terrain only found north-west of the River Tees-River Exe line.
The upland areas include the Lake District, the Pennines, the North York Moors, Exmoor, and Dartmoor.
The lowland areas are typically traversed by ranges of low hills, frequently composed of chalk, and flat plains.
Scotland is the most mountainous country in the UK and its physical geography is distinguished by the Highland Boundary Fault which goes across the Scottish mainland from Helensburgh to Stonehaven.
The Royal Observatory, Greenwich is the defining point of the Prime Meridian.
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.
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.
Queen Elizabeth II is the Queen 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 Boris Johnson, 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 Queen.
The House of Commons is the most powerful part.
It is where Members of Parliament sit.
The Prime Minister sits here as well because they are a Member of Parliament.
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.
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 (Her 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.
Unlike the House of Commons, the people in the House of Lords are not elected.
The people who sit in the House of Lords are called peers.
Most peers are appointed by the government.
There are some who are hereditary peers (who inherit their peerages from ancestors or other family members).
Certain bishops in the established Church of England also attend the House of Lords. (
The Church of England is the national church in England.
The Church of Scotland does not have bishops, and neither Wales nor Northern Ireland has an established national church.)
Together, the two houses make a bicameral legislature, in which the House of Commons has more power.
In the past, the House of Lords had more power.
Before the 20th century, the prime minister was often a member of the House of Lords.
As the House of Lords lost its powers, as political reforms tried to improve democracy, the House of Commons became more powerful and the prime minister started always to be a member of the House of Commons.
After the English Civil War during the Wars of the Three Kingdoms, Oliver Cromwell became Lord Protector, and the monarchy ended for a time.
The British Isles were a republic, which Cromwell named the "Commonwealth of England, Scotland, and Ireland".
Although the monarchy was restored after his death, the Crown slowly became the secondary power, and Parliament the first.
Until the early twentieth century, only men who owned property could vote to choose MPs.
In the nineteenth century, more people were given suffrage.
In 1928, all men and women got the vote: this is called universal suffrage.
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 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, but 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 some responsibility in international law.
Man, Jersey, and Guernsey are "crown dependencies".
Some British Overseas Territories have their own legislatures.
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.
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 (For it was the wealthiest country at the time.)
and in military strength.
Britain continued to be the biggest manufacturing economy in the world until 1908 and the largest economy until the 1920s.
The economic cost of two world wars and the decline of the British Empire in the 1950s and 1960s reduced its leading role in global affairs.
The United Kingdom has strong economic, cultural, military and political influence and is a nuclear power.
The United Kingdom holds a permanent seat on the United Nations Security Council, and is a member of the G8, NATO, World Trade Organization and the Commonwealth of Nations.
The City of London, in the capital, is famous for being the largest centre of finance in the world.
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.
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 schools (known as public schools).
There have been universities in Britain since the Middle Ages.
The "ancient universities" started in 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 from the Russell Group of research universities.
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.
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 high speed motorway (freeway) network was mostly constructed in the 1960s and 1970s and links together 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 within 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, whilst 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.
Brittonic or Bythonic languages
Goidelic or Gaelic languages
Irish Gaelic
Ulster Scots
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.
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 it’s size never ends as it has been expanding since the Big Bang.
People have long had ideas to explain the Universe.
Most early models had the Earth at the centre of the Universe.
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 led astronomers to realize that the Solar System is in a galaxy made of billions of stars, which we call the Milky Way.
They also realized that 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).
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.
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; thus, 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 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 and possibly infinite in volume.
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.
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 11–20 billion years.
The Universe has not been the same at all times in its history.
This getting bigger accounts for how Earth-bound people can see the light from a galaxy 30 billion light-years away, even if that light has traveled for only 13 billion years; the very space between them has expanded.
This expansion is consistent with the observation that the light from distant galaxies has been redshifted; the photons emitted have been stretched to longer wavelengths and lower frequency during their journey.
The rate of this spatial expansion is accelerating, based on studies of Type Ia supernovae and other data.
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
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.
General relativity provides of a set of ten nonlinear partial differential equations for the spacetime metric (Einstein's field equations) that must be solved from the distribution of mass-energy and momentum throughout the Universe.
Since these are unknown in exact detail, cosmological models have been based on the cosmological principle, which states that the Universe is homogeneous and isotropic.
In effect, this principle asserts that the gravitational effects of the various galaxies making up the Universe are equivalent to those of a fine dust distributed uniformly throughout the Universe with the same average density.
The assumption of a uniform dust makes it easy to solve Einstein's field equations and predict the past and future of the Universe on cosmological time scales.
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