WHEN will the final results come in?

Polls closed about 10 p.m. local time (5 p.m. Eastern) on Thursday, and no formal exit poll will be released.

This means that only when the first vote counts start being released about midnight U.K. time, will we get our first picture of what the result might look like.

Votes will be counted until one side reaches a number that is mathematically unbeatable, which may take a while given how close the vote is expected to be.

It's thought that from early morning U.K. time, perhaps about 2 a.m. for those of us on Eastern time, the final outcome of the vote should be clear.

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What happens if 'leave' wins a majority?

This is a little complicated. No country has ever voted to leave the European Union before, and it's not clear how things should proceed.

What we know is that British Prime Minister David Cameron will be expected to trigger Article 50 of the Lisbon Treaty, which is the mechanism for a country to leave the European Union.

We don't know exactly when he would do so, although he has suggested that he would trigger it immediately, and EU leaders would push him to do so quickly.

It is possible that Cameron could opt not to invoke Article 50, perhaps instead repealing the 1972 European Communities Act and withdrawing from the European Union unilaterally. However, such a move probably would anger many EU member states with which Britain will soon be seeking a deal and force Britain to immediately legislate to replace EU laws with no transition period.

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How does Article 50 work?

The article sets out how Britain would negotiate its terms for leaving the European Union. Britain would not negotiate directly with member states. Instead the member states would meet among themselves as the European Council and agree on a framework. Britain would then negotiate on the technical details with the European Commission. The European Parliament also will have a say, giving consent on the deal.

Sounds complicated? It is. And it's unprecedented, so it's not clear exactly what it looks like or how long it would take. The article clearly states that a country will have two years to reach an agreement on the exit, during which time the country would still be governed by EU treaties and laws, although it will not be allowed in the decision-making process. However, if all EU member states agree, that deadline could be extended.

It's also worth noting that Article 50 does not have a provision that allows a country to back out of the process. And if Britain ever decides it wants to be in the European Union again, it will have to go through the same process as any other applicant country.

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Then what?

Britain will have to strike new trade deals with Europe and amend its laws that were based on EU legislation. It will take a long time to sort all of that out.

For one thing, it's still unclear exactly what sort of relationship Britain will be able to strike with the European Union. As my colleague Griff Witte has reported, there are essentially four models ranging from what Norway or Iceland has - in which Britain would be a member of the European Economic Area and essentially keep access to the European common market - to simply no deal at all, falling back on its membership of the World Trade Organization to set terms of trading.

Many suspect that the European Union may try to "punish" Britain and deter other countries from making their own exit with a lousy deal. However, if the economic fallout is as bad as some have predicted, it's also possible that European leaders may seek to calm markets with a quick and easy deal.

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Will Parliament agree?

The Brexit referendum isn't binding in itself; any deal will have to be approved by Britain's Parliament. This means that pro-remain MPs - i.e. the majority of Parliament - may try to block any deal that they think doesn't give the country enough access to the European Union. The pressure could in turn lead to calls for a new general election.

It does seem unlikely that British MPs would flagrantly go against the wishes of the electorate by totally blocking a Brexit, but they could well use their power to influence negotiations.

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Will Cameron resign?

Cameron gambled by calling the referendum. If "remain" loses, he will have lost that gamble. Although the prime minister has said he would not resign in the wake of a vote for Brexit, many in Britain will expect him to resign. It's possible that he may not do so right away - he may set a timetable to step down or wait for a leadership challenge. If the economic fallout is particularly bad, he may argue that he needs to stay in office to help steer Britain back on course, a process that could take months.

Boris Johnson, the colorful former mayor of London, who was a loud voice in the Brexit campaign, is likely to be the favorite for new leader of the Conservative Party. However, his time in office may not last long. If a new leader of the Conservatives is selected, there will be pressure for the leader to call a general election.

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What would happen to the financial markets?

This all means a lot of uncertainty for a considerable amount of time, and uncertainty is something markets do not like. Many expect the value of the pound to immediately drop on Friday if Britain votes out - investor George Soros has suggested a drop of 15 percent to 20 percent. The euro is also expected to lose some value in the short term at least.

Stocks also are expected to be hit, with British Chancellor George Osborne hinting this week that he could suspend trading on London's stock market on Friday if Britain votes out of Europe. The financial impact is likely to be global, with implications for American readers, too.

A wide variety of financial institutions have made dire predictions about the long-term economic effects of a Brexit. Of course, these are predictions. What will happen ultimately isn't certain, but short-term pain for Britain and others seems very likely.

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What would happen to the European Union?

The vote will definitely shake the grand European vision. It will certainly provide fuel for anti-EU politicians all over the continent. Recent polls have shown that countries such as France and Italy want their own votes on EU membership, and populists such as the French National Front's Marine Le Pen have found Euroskepticism to be a powerful message to voters.

At the least, it will give the European Union another logistical problem at a time when it has many others already to deal with, including the refugee crisis, the economic issues across the euro zone and the continuing threat of Russian aggression.

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But what happens if 'remain' wins?

In theory, nothing will really change. Britons would have voted to keep the status quo. Cameron probably will give a statement outside No. 10 Downing Street early Friday. Financial markets, which had been fearful of the uncertainty, will be buoyed. The pound and the FTSE 100 stock market index probably will rise.

Some doubts will remain, however. Although Cameron is likely to stay in office in the immediate term, the election will have revealed the deep divisions within his Conservative Party. It's unclear how Cameron will treat senior members of his party who led the "leave" campaign. He may try to keep these politicians, namely Johnson and Michael Gove, close to him in a bid to calm his party's divisions, although most suspect he'll wait until the party conference in October before reshuffling his cabinet.

On the other hand, if the vote is especially close, Cameron could face a leadership challenge regardless of the fact that his campaign won. Pro-Brexit leader Nigel Farage has also suggested that there should be a second referendum if the vote is close, although other politicians have said this should not be a possibility.