The United Kingdom of Great Britain and Northern Ireland, commonly known as the United Kingdom (UK) or Britain, is a sovereign state in Europe. Lying off the north-western coast of the European mainland, it includes the island of Great Britain, the north-eastern part of the island of Ireland and many smaller islands. Northern Ireland is the only part of the UK that shares a land border with another state - the Republic of Ireland. Apart from this land border, the UK is surrounded by the Atlantic Ocean, with the North Sea to its east, the English Channel to its south and the Celtic Sea to its south-southwest. The UK is the 80th-largest sovereign state in the world and the 11th-largest in Europe. It is also the 21st-most populous country, with an estimated 64.5 million inhabitants.
The total area of the United Kingdom is approximately 243,610 square kilometres (94,060 sq mi). It lies between the North Atlantic Ocean and the North Sea with the south-east coast coming within 22 miles (35 km) of the coast of northern France, from which it is separated by the English Channel. The United Kingdom lies between latitudes 49° to 61° N, and longitudes 9° W to 2° E. Northern Ireland shares a 224-mile (360 km) land boundary with the Republic of Ireland. The coastline of Great Britain is 11,073 miles (17,820 km) long. It is connected to continental Europe by the Channel Tunnel, which at 31 miles (50 km) (24 miles (38 km) underwater) is the longest underwater tunnel in the world.
The UK service sector makes up around 73% of GDP. London is one of the three "command centres" of the global economy, it is the world's largest financial centre alongside New York, and it has the largest city GDP in Europe. Edinburgh is also one of the largest financial centres in Europe. Tourism is very important to the British economy and, with over 27 million tourists arriving in 2004, the United Kingdom is ranked as the sixth major tourist destination in the world and London has the most international visitors of any city in the world. The creative industries accounted for 7% GVA in 2005 and grew at an average of 6% per annum between 1997 and 2005.
Research and Development
Scientific research and development remains important in British universities, with many establishing science parks to facilitate production and co-operation with industry. Between 2004 and 2008 the UK produced 7% of the world's scientific research papers and had an 8% share of scientific citations, the third and second highest in the world (after the United States and China, respectively).