Voting has ended in the highly anticipated general election in the United Kingdom. It will determine the fate of Gordon Brown's Labour government, which has been in power for the past 13 years.

The casting of ballots across England, Scotland, Wales and Northern Ireland caps a month-long election campaign marked by Britain's first-ever televised debates among the leaders of the three main parties.

The Conservatives, led by David Cameron, are hoping to return to power after 13 years as the opposition.

Observers believe this election is likely to be the closest since 1992, when the Conservatives were returned to power. For that reason Nick Clegg and the Liberal Democrats - known as the "third force" of UK politics - may have a crucial role to play after election day in helping either party secure a parliamentary majority.

On a more localized level, smaller parties, as well as national parties in Scotland, Wales and Northern Ireland, are likely to have an impact on voters in their constituencies.

So what do you need to know?

Conservative Party leader David Cameron, left, Liberal Democrat leader Nick Clegg , middle, and Prime Minister Gordon Brown await their fate in the U.K. general election.

If you're in the dark about how things work in the U.K. you can check out our explainer on how the political system and elections work in the U.K. Then, follow as election results and details come in on our U.K. election blog, on Twitter by following @UKelectionCNN and tune into CNN’s UK election coverage with Becky Anderson and Richard Quest on CNN.com/Live or on CNN’s iPhone app starting at 5 p.m. ET Thursday.

Meanwhile, we'll try and break down the rest of the details for you right here - starting with the key figures.

Who’s running?

• Labour leader Gordon Brown is fighting to stay in office in as bad a political climate as could be imagined. CNN’s Peter Wilkinson profiles Brown, who is facing the electorate after his party has been in power for 13 years.

• Tory leader David Cameron has been tipped as a prime minister-in-waiting - is this election his big chance? CNN's Simon Hooper looks at whether Cameron, who is credited with reviving the center-right opposition Conservatives, can capitalize in this election.

• For years his party has failed to make a big impact in U.K. elections - now Liberal Democrat Nick Clegg may play kingmaker. CNN's Richard Allen Greene profiles Clegg, who hopes a close election may mean a bigger role for him.

Could election be too close to call and create a "hung parliament?"

Many people believe because the race is so close - it may well end without a definite result. One of the parties will have to win a minimum of 326 seats to take the majority - more than half the total of 650 being contested.

If any party is unable to win a governing majority it could create a "hung parliament," essentially a deadlock. Without a majority in parliament, a government becomes dependent on MPs - or lawmakers - from other parties to get its program voted through the House of Commons, the chamber which passes laws and legislation.  How can this happen and what does it mean? CNN's Political Contributor Robin Oakley, a veteran of 12 UK elections, explains what could happen and why.

What would happen next?

The party with the most seats could try and form a minority government or launch a partnership in a coalition government.

• In a minority government a party tries to rule without a majority by winning support from other MPs on a vote-by-vote basis
• In a coalition government two or more parties agree to an alliance that sees them top the 326 majority to a shared agenda.
• Liberal Democrat leader Nick Clegg has said he would want promises of electoral reform before he joined a coalition government. And this may be unpalatable for the Conservative or Labour leaders whose parties have dominated the British political system for the last 100 years. Clegg would likely demand switching to a proportional representation system which would award seats based on the total number of votes rather than individual races, thus giving new power and voice to the Liberal Democrats, who have broad support but often come in second.

If you haven't been able to wrap you're head around that and just want to take a peek at where all the action will take place as a tourist, you can always check out our panoramic view of Parliament Square.