[quote]Definition Withdrawal of the United Kingdom from the European Union, often shortened to Brexit (a portmanteau of "British" or "Britain" and "exit"),[1][2] is a political goal that has been pursued by various individuals, advocacy groups, and political parties since the United Kingdom (UK) joined the precursor of the European Union (EU) in 1973. Withdrawal from the European Union is a right of EU member states under Article 50 of the Treaty on European Union. In 1975, a referendum was held on the country's membership of the European Economic Community (EEC), later known as the EU. The outcome of the vote was in favour of the country continuing to be a member of the EEC. The UK electorate will again address the question on June 23, 2016, in a referendum on the country's membership. This referendum was arranged by parliament when it passed the European Union Referendum Act 2015. [Wikipedia] [b]FAQ[/b] What will be the larger effect on geopolitics if the UK were to leave? A very likely possibility is a new referendum on Scottish independence. A big argument for the no vote in the last one was that membership in the EU wasn't assured in the case of independence. If Scotland votes to Remain (which is the most likely outcome), while the rest of the UK votes to Leave the EU, Scots might feel that they were cheated into staying in the UK, and it's very likely that the SNP would seize that opportunity to push for a new referendum. And this time the result might be different. There is likely to be little change for the time being, since exit is going to be about two years away in reality. Britain will remain in NATO. The big thing is that the Britain will likely start trying to make trading agreements with other countries/regions such as within the commonwealth and as such those agreements will affect other blocs wishing to make agreements in those regions. since it's not the EU making the agreement and all the associated politics of the many nations coming into play, Britain may be able to make agreements more nimbly. tldr; not much for the first few years. Is today's vote final? I mean, whether they vote to stay or leave... can the decision be reversed by the government/be brought up again for voting next year, for example? Short answer: No, the vote is not binding. Long answer: The vote is not binding, but gives an indication on where the people of the UK stand on this issue, which can be used to determine what the government should do in this situation. Whatever the outcome, this is not the last we'll hear of a Brexit. If the remain vote wins, that means that nearly half the country wants to leave the EU. If the leave camp wins, that means that nearly half the country wants to remain in the EU, and that Scotland will probably ask for a new referendum on independence from the UK. It's going to be close, and whatever the outcome: the government can't just ignore what nearly half the country wants, just because the other side won by a few percentagepoints. What does it mean exactly? That they're not a part of Europe? Or is it something else? The European Union Explained in 6 minutes https://youtu.be/O37yJBFRrfg Why is this such a huge issue, and why is it so divisive? I would think being a member of the EU is objectively a good thing. There are some issues which people take as a reason to leave. As a large political body there is a fair amount of red-tape involved in the EU. Some think we would be better off without that. In a similar vein, some disagree with policy being made by a body which they feel is unaccountable (we do vote for MEP's but since it is a large number of voters, the value of a single vote for the European elections is less than, say, a national or local election) The EU guarantees freedom of movement for citizens of it's member states. This means that people from poorer countries (ie eastern europe) can move to richer countries (ie western europe) in order to find work. The indigenous populations sometimes take exception to this because they feel that people who work harder for less money are putting them out of work (mostly true of the unskilled manual labour sector) In any system of government money often is taken from the richer sections of society and is used to support the poorer sections of society. There are those who feel the money that we pay into the EU does not directly benefit us and if we left the EU we could keep the money ourselves (ie charity starts at home) Some of the longer term goals of the union is more integration and a unified Europe. There are some sceptical of these goals because they believe we would never get along because our cultures are too different and we don't speak the same languages. In continental Europe there is a trend for people to speak a second language, something that has never happened in the UK which amplifies an "us and them" mentality [/quote]