Voting in the UK general election is under way at more than 40,000 polling stations across the country.
Polls opened at 07:00 BST on Thursday, with counting starting once voting ends at 22:00 BST.
A total of 650 Westminster MPs will be elected, with about 46.9 million people registered to vote.
That is up from the last general election, in 2015, when there were 46.4 million registered voters.
Some votes have already been cast, through postal voting, which accounted for 16.4% of the total electorate at the 2015 general election. People with an undelivered postal vote can still deliver it by hand to their local polling station.
Overall turnout in 2015, when the Conservatives won 331 out of 650 seats, was 66.4%, up from 2010.
Most polling stations are in schools, community centres and parish halls, but pubs, a launderette and a school bus have been used in the past.
Police have increased security at polling stations, including patrols by armed officers in some areas, following the recent terror attacks.
A handful of seats are expected to be declared by midnight, with the final results expected on Friday afternoon.
Unusually, no local elections are taking place at the same time, so results might come through earlier than in recent general elections.
In 2015 the first seat to declare was Houghton and Sunderland South, at 22:48 BST.
To form a majority in the House of Commons one party must win 326 seats – in 2015 a Conservative majority was not confirmed until 13:34 BST.
The weather forecast is for some rain in south-west England, Northern Ireland, Scotland and Wales on Thursday, with south-east England remaining cloudy and dry.
Polls close at 22:00 BST, but officials say anyone in a polling station queue at this time should be able to cast their vote.
The BBC’s main election programme, fronted by David Dimbleby, starts at 21:55 BST, with live coverage from scores of counts.
Dimbleby, fronting his 10th election night broadcast, will be joined by Mishal Husain, Emily Maitlis, Jeremy Vine.
Wales, Scotland and Northern Ireland will have their own overnight programmes but will join Huw Edwards from 07:00 BST on 9 June.
On the radio, an overnight broadcast by BBC Radio 4 will be hosted by Jim Naughtie and Carolyn Quinn.
On BBC Radio 5 live, the overnight show will be hosted by Stephen Nolan and Emma Barnett.
Full coverage of the results as they come in will be on the BBC politics online live page and front page scorecard, with all the big breaking stories from around the country and analysis by correspondents
What you need to know about the election:
If you are on the electoral register, you should have received a polling card through the post which has your name, polling number and the address of your polling station printed on it.
Polling stations are usually set up in public buildings such as schools, community centres and village halls near where you live.
If you have not received a polling card but think you should have, contact your local authority’s election office.
If you have lost your polling card, the office will be able to tell you where your polling station is.
To find the contact details of your local office, enter your postcode on the About My Vote website.
Do I need to take my polling card with me?
No. The polling card is for your information only, but taking it to the polling station can speed up the process.
Can I go to any polling station?
No. You must vote at the polling station to which you have been assigned.
Any voter who has not had a chance to post their postal vote (if they have asked for one) can still take it to their polling station.
What do I do when I get to the polling station?
When you arrive, staff will take your details and cross off your name on their checklist. In Northern Ireland, staff will also ask for a form of photographic ID.
What happens next?
You will be given a ballot paper listing candidates and parties you can vote for. It will be printed on special paper or feature an official mark or number to combat fraud.
Then I vote?
Yes. Take the ballot paper to one of the booths, which are screened to ensure secrecy.
Each polling booth should include sharpened pencils, attached to string long enough to accommodate both right and left-handed voters. You can use you own pen or pencil if you prefer.
Read the ballot paper carefully before you vote.
How do I vote?
Put an X in the box next to the name of the person you want to vote for. If you mark any more boxes, your paper will be invalid.
Can I put a smiley face instead?
The Electoral Commission says the best way to make sure your vote is counted is to mark an X in a box. But a smiley face or anything which is interpreted by a returning officer as an expression of preference “must not be rejected if the voter’s intention is clear”, its guidance to Returning Officers says.
What do I do with my marked ballot paper?
Fold the ballot paper so others cannot see your choice and post it in the ballot box.
What if I make a mistake?
Don’t worry. You can get your ballot paper reissued, so long as you have not put it in the ballot box.
Can I spoil my ballot paper?
Yes. The verification of the used, unused and spoilt ballot papers is a legal requirement. Some people spoil their votes as a means of registering their democratic right to express a view, but not vote for any of the candidates.
I have got a disability. Can I get help?
Yes, everyone has the right to request assistance to mark their ballot paper. You can do this by asking the presiding officer to mark the paper for you. Or bring a close family member who is over 18, or someone who is eligible to vote at the election, such as a support worker, with you.
If you have a visual impairment, you can ask for a special voting device that allows you to vote on your own in secret. A large print version of the ballot paper should also be clearly displayed in the polling station.
Returning officers must also consider accessibility requirements when planning for an election, and polling stations are selected in consultation with local disability groups so that wheelchair ramps and disabled parking spaces are available.
If a voter cannot enter the polling station because of a physical disability, the presiding officer may take the ballot paper to the elector.
I have a learning disability. Can I get help?
Yes. If you need help, call the Electoral Commission’s public information line on 0333 103 1928.
A dedicated helpline for anyone with a learning disability who has questions about casting their vote, or experiences any difficulties in doing so, has also been set up by Mencap, a partner of the Electoral Commission.
The helpline is also available to the families and carers of people with learning disabilities, and to polling station staff. The number is 020 7696 5588.
What if I cannot get to a polling station?
If you are suddenly incapacitated or taken ill on polling day, you can apply for an emergency proxy up until 17:00 BST on the day.
I forgot to register, can I vote?
No. You cannot vote unless you are on the electoral register.
Is it compulsory to vote?
No, people cannot be forced to vote.
When will I know the result?
The votes will start to be counted as soon as the polls close at 22:00 BST. Constituencies will start to declare within the first few hours of the vote, with a large number expected between 03:00 BST on Friday and 05:00 BST. It is difficult to predict when a new government will be formed, and depends on how close the election is.