Britain has become the first nation to leave the European Union. The EU is an economic and political partnership involving 28 European countries, namely; Austria, Belgium, Bulgaria, Croatia, Cyprus, Czech Republic, Denmark, Estonia, Finland, France, Germany, Greece, Hungary, Ireland, Italy, Latvia, Lithuania, Luxembourg, Malta, Netherlands, Poland, Portugal, Romania, Slovakia, Slovenia, Spain, Sweden, United Kingdom. 
The UK Independence Party campaigned for Britain’s exit from the EU. They said Britain was being held back by the EU, which according to them imposes too many rules on business and charges billions of pounds a year in membership fees for little in return. They also wanted Britain to take back full control of its borders and reduce the number of people coming here to live and/or work.
Barrack Obama, British Prime Minister, David Cameron who wanted Britain to stay opined that it gets a big boost from membership – it makes selling things to other EU countries easier and, they argued, the flow of immigrants, most of whom are young and keen to work, fuels economic growth and helps pay for public services. They also said Britain’s status in the world would be damaged by leaving and that we are more secure as part of the 28 nation club, rather than going it alone.

Votes were however cast, the Leave campaign garnered about 51.8 per cent of the vote. There were 33,577,342 votes cast with Remain securing 16,141,241 votes and Leave 17,410,742.
How long will it take Britain to leave? The minimum period after a vote to leave will be two years. During that time Britain will continue to abide by EU treaties and laws, but not take part in any decision-making
Additional information from BBC