Britain is a parliamentary democracy, meaning that the government is formed from lawmakers rather than being separately elected. With the upcoming negotiations on Britain quitting the European Union left to the winner of the snap poll, the stakes could hardly be higher.
For the election to produce a majority government, the biggest party theoretically must win at least 326 seats of the 650 regional constituencies. But in practice, the threshold for a majority is around 323, because the Irish republican Sinn Fein party does not take up any seats it wins in Northern Ireland.
The eve of the UK elections saw quite a bit of activity on both sides of the major parties fighting the elections: the Conservative Party and the Labour Party. Conservative Prime Minister Theresa May and main opposition Labour leader Jeremy Corbyn were criss-crossing the country on Wednesday, targeting urban areas whose votes could be crucial.
However, many have also said that this lead over the opposition Labour party has ebbed over the last three weeks, with some even putting her majority in doubt. An upbeat Corbyn said the party's chances had been underestimated, as he promised to reverse cuts rolled out under the Conservatives.
(With inputs from agencies)
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