Voters go to the polls in the UK's third general election in less than five years – and the fourth in less than a decade.
After a six-week campaign, the country will decide whether Conservative Party Boris Johnson or Labor's Jeremy Corbyn will form a government for up to five years.
A total of 650 parliamentary constituencies are being contested in England, Scotland, Wales and Northern Ireland, with polling stations open from 7 am to 10 pm.
The total electorate is about 46 million and there will be 40,000 polling stations. Unusual locations include several bars, a hair salon, a laundromat, a chip shop and a windmill.
When all votes are counted after polls close, a party needs 326 seats for the majority at Commons, not counting on the support of smaller parties.
It is the first December general election since 1923 and the first winter election since February 1974, when Edward Heath and the Conservatives were defeated by Harold Wilson's Labor Party.
In the last three general elections, in 2010, 2015 and 2017, only one – when David Cameron triumphed in 2015 – produced a clear winner, with a party securing the general majority of Commons.
More on General Elections 2019
Labor Party leader Jeremy Corbyn is struggling to become prime minister
In 2010, after Conservatives fell short of the majority, Cameron entered a coalition with Nick Clegg's Liberal Democrats.
And in 2017, after the second parliament suspended in seven years, Theresa May was forced to strike a deal with the Northern Ireland Democratic Union (DUP) to keep conservatives in power.
After leading opinion polls throughout the 2017 campaign, the final results saw conservatives gain 318 seats, losing 13. Labor won 262, winning 30.
The SNP count dropped from 56 to 35 and Liberal Democrats rose from eight to 12. The turnout was 68.7%.
Visit Sky News Brexit Electoral Studio
Conservatives are battling 635 seats, Labor 631, Liberal Democrats 611, SNP All 59 in Scotland, Plaid Cymru 36 in Wales, Green Party 474 and Brexit Party by Nigel Farage 276, after withdrawing of all seats currently held by conservatives.
Boris Johnson expects voters to give him the majority
As always, this election was dominated by party leaders. While Johnson and Jo Swinson of the Lib Dems, who, as the prime minister, became party leaders in July, fight in their first campaign leading their party, is Corbyn's second position as a labor leader.
He is the first Labor leader to fight more than one election as a leader since Tony Blair, who won in 1997, 2001 and 2005, and the first since Neil Kinnock to fight a second campaign after an election defeat.
And the time for this first winter election for almost a century?
Jo Swinson of Lib Dems says she wants to become prime minister
The forecast for voting day is uncertain, with prolonged rainfall for many, according to Sky News news producer Chris England.
"Thursday morning will bring clouds and bouts of rain for most and snow for the northern hills, but Scotland and eastern England will be mostly dry and bright," he says.
"There will only be a strange bath there.
"Most places get colder again but get softer in the southwest.
"Southern and central Scotland will be humid in the afternoon, while Wales and southwestern Britain and Ireland will see the rain give way to more scattered rainstorms.
Brexit's election on Sky News – the fastest results and in-depth analysis on mobile, TV and radio.
- Watch John Bercow with Dermot Murnaghan Live from 21:00 on Thursday
- Follow the Election Social show hosted by Lewis Goodall and Emily Ashton of BuzzFeed UK on the Sky News website, the app and social media channels also starting at 9:45 pm.
- View the 10pm live exit poll
- Watch KayBurley @ Election Special Breakfast Friday Morning