The countdown has begun for this year's Eurovision song contest, which will be broadcast live from Liverpool in May.
The UK is staging the contest on behalf of 2022 winners Ukraine.
When is Eurovision?
The Eurovision final will take place at the M&S Bank Arena on the waterfront in Liverpool on Saturday 13 May.
It will be the first Eurovision Song Contest to be held in the UK for 25 years.
The competition is made up of two semi-finals and the grand final - all of which will be broadcast live.
This year's semi-finals will take place on Tuesday 9 May and Thursday 11 May, with ten countries from each show going through to the final.
In addition, the UK, Italy, France, Spain and Germany are already guaranteed a spot, along with last year's winners, Ukraine.
This means 26 countries will compete in the final.
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Who will represent the UK?
Mae Muller will represent the UK with her track I Wrote A Song, the country's first female Eurovision entrant for five years.
She was born in 1997 - the year the UK last won Eurovision - and has previously supported Little Mix on tour.
As in recent years, there was no televised national selection show.
Instead, the BBC chose the winner in consultation with a management company.
All of the other participating countries have revealed their songs and acts.
Tickets for all of the Eurovision shows went on sale at 12:00 GMT on Tuesday 7 March and sold out almost immediately.
As well as the three televised live shows - the semi-finals and the final - there are six preview shows which double as dress rehearsals.
Prices ranged from £90 to £290 for the live semi-final shows, and from £160 to £380 for the live grand final. Preview show tickets cost between £30 and £280.
About 3,000 tickets are being made available to Ukrainians living in the UK.
How can I watch Eurovision?
More than 160 million people around the world are expected to watch the 2023 final.
In the UK, Eurovision will be broadcast live on BBC One.
The BBC's coverage will be hosted by Graham Norton, Hannah Waddingham, Alesha Dixon and Ukrainian singer Julia Sanina.
In addition, a special fan zone will accommodate up to 25,000 people at Liverpool's Pier Head, close to the arena.
Events planned include a submarine parade through the city and a rave which will take place simultaneously in Liverpool and Kyiv.
Why is the UK hosting Eurovision?
Ukraine's Kalush Orchestra won the 2022 Eurovision song contest with their song Stefania.
Normally, the winning country hosts the following year's competition, but the ongoing war in Ukraine makes this impossible.
The European Broadcasting Union (EBU), which organises the contest, invited the UK to host on Ukraine's behalf because UK contestant Sam Ryder was the runner up in the 2022 show.
It will be the ninth time the UK has hosted the competition, and the fifth time it has done so on behalf of another country.
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How much does Eurovision cost?
Broadcasters from the 37 countries taking part each pay an entrance fee to the EBU. In recent years these fees have totalled about £5m. The BBC does not make its contribution public.
Russia was expelled from the competition following its invasion of Ukraine.
BBC News has been told countries have been asked to pay more to make up for its loss. Three countries have said they will not take part as a result of the increase.
Some broadcasters are also thought to be worried about the additional costs of transporting equipment to the UK now it is no longer a member of the EU.
Staging the event is expected to cost the BBC between £8m and £17m.
The UK government has pledged £10m towards operational costs, while local authorities in Liverpool have committed £4m.
How does the voting work?
The semi-finals are decided by a public vote, but the final is more complicated.
Each of the 26 countries has a jury whose members rank all the final performances.
They award a fixed number of points to their top 10 acts: Respectively 12 points, 10 points, eight, seven, six, five, four, three, two and one.
The jury results are announced by each country in turn on the night.
Competing countries then award points to the other contestants based on viewer votes, following the same scoring system.
For the first time, in 2023 public votes from outside Europe will play a part. Worldwide votes will be combined and counted as if they are another country.
Why does Australia take part in Eurovision?
Eurovision has long been popular in Australia, and in 2015 it was invited to send an act as part of the contest's 60th anniversary celebrations.
It has been allowed to take part ever since. Like European countries, it pays a fee to the EBU to help fund the event.
However, Australia is barred from hosting. If it ever won, it would have to nominate a European nation to stage the contest on its behalf.
Other non-European countries, including Israel, are also allowed participate because they are members of the EBU.
Source: BBC