After months of trading long-range barbs during the 2020 US election campaign, President Donald Trump and Democratic nominee Joe Biden will meet face-to-face on the debate stage today.
It's the first of three presidential debates between the two candidates before the US election on November 3.
Here are five quick questions to bring you up to speed.
1. When is the first presidential debate? And other important bits to know
The first debate will be held today from 11:00am — 12:30pm AEST.
The venue is the Case Western Reserve University in Cleveland. The original venue was the University of Notre Dame, but the university withdrew because of the coronavirus pandemic.
The moderator will be Fox News host Chris Wallace.
It'll be divided into six 15-minute segments, chosen by Wallace:
- The Trump and Biden records
- the US Supreme Court
- the economy
- the integrity of the election
- race and violence in cities
The questions on each topic are a closely guarded secret, and each candidate will get two minutes each to respond.
Don't leave your seat: The debate won't have any commercial breaks. Once it starts, it doesn't stop till it's over.
2. What do we know about the moderator?
Chris Wallace is a veteran Fox News host and normally anchors the flagship Fox News Sunday show.
He's famous for his polite but uncompromising interviews with American politicians from both major parties.
Wallace hosted the third presidential debate in 2016 between Donald Trump and Hillary Clinton, and won praise for his tough questioning and fair moderation of the debate.
He did face criticism prior to the 2016 debate for saying he didn't believe it was his job to be a "truth squad" when asked how he would deal with potential lies from the candidates.
Try a preview: Here are the best bits from Wallace's recent viral interview with the President where the pair clashed about coronavirus statistics and Mr Trump warned he may not accept the results of the 2020 election.
3. How will things be different because of COVID?
There will be no handshakes. Neither candidate will wear a mask. The podiums will sit roughly two metres apart.
And there will be a small, ticketed crowd in attendance, as well as a select number of journalists, campaign staff and organisers.
Peter Eyre, the senior advisor for the Commission on Presidential Debates told reporters that all attendees will be required to take a COVID-19 test within 72 hours of the debate but did not say what sort of requirements would need to be met in order to attend.
Joe Biden's been here before: The last of the Democratic Primary Debates was held without a live audience. It may have been a factor in Biden's blunder-free performance.
4. How are the candidates preparing?
Donald Trump is reportedly skipping traditional debate prep of facing off against someone pretending to be Joe Biden in a mock debate, according to NBC.
In an interview with Fox News, Mr Trump said he was "sort of" preparing for the debates by "just doing what I'm doing", referring to his appearances at rallies in swing states.
Former vice-president Biden is also reportedly shunning mock debates in favour of research briefings and tough questions from aides, according to The Atlantic.
Speaking at a fundraiser, Mr Biden said he hopes he doesn't "take the bait" from the President in the debates.
"I hope I don't get baited into a brawl with this guy, because that's the only place he's comfortable," Mr Biden said.
Practice makes perfect: Both candidates appeared at separate town hall events hosted by US TV networks and took questions from voters in recent weeks.
5. What happens next?
Buckle up, this is just the beginning of a month-long series of debates in the run home to the election on November 3.
Next week is the first and only vice-presidential debate between Kamala Harris and Mike Pence.
The week after that will be the second presidential debate, a town-hall style format where both candidates will be grilled by voters.
The final presidential debate happens on October 22. It will be the same format as the first debate.
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