It's all over but the talking.

President Joe Biden and former President Donald Trump are set to take the stage Thursday evening in the first debate of this year's presidential campaign - one that is laden with historical significance and political consequences for both men. 

The debate is the first in history between a sitting president and a former chief executive. 

The contest is also the first time the Democratic and Republican rivals will face-off with each other since the 2020 debates, and it will be the first time this election cycle that the two have even appeared on a debate stage. 

Trump opted out of debating his Republican rivals during the GOP primary.

And it's happening earlier than other past debates - even before neither Biden nor Trump has been formally nominated by their parties yet. 

Here's how to watch:

What time is the debate?

The 90-minute debate from Atlanta will air on CNN beginning at 9 p.m. ET. It will also air live on CNN International, CNN en Espanol, and will be live streamed on CNN MAX. Other networks will also air the debate with a feed provided by CNN.

 Who are the debate hosts?

CNN anchors Jake Tapper and Dana Bash.

What are the debate rules?

The debate will take place without a studio audience. Biden and Trump will be behind podiums about eight feet apart on stage. They will not be allowed to have props or pre-written notes. They will have a pen, a pad of paper and water.A noted change this time is that the other candidate's microphone will be muted while the other is speaking.There will be two commercial breaks.

Will Robert F. Kennedy Jr. be on the stage?

The third party candidate failed to meet the qualifications for the debate - which required polling at 15% or higher in a number of national surveys and secured spots on enough ballots necessary to compete for 270 Electoral Votes.

What's at stake for each candidate?

One of the biggests questions for the debate is whether Biden, at 81 the oldest president in U.S. history, can dispel concerns about his age, and his physical and mental capabilities to lead the country for another four years. Trump and his GOP supporters have launched numerous attacks on the president's vigor in the past and have highlighted his gaffes to show that he is unfit for office. Trump is expected to press Biden on the economy and his immigration policies.

At the same time, the 78-year-old Trump has come under scrutiny for his own flubs in campaign speeches. Trump is also burdened with his conviction on 34 felony counts from his hush-money trial in Manhattan and has been indicted in three other cases. Biden, for his part, is expected to hammer the former president on the Supreme Court's decision to overturn Roe v. Wade.Trump nominated three of the justices who voted for Roe.  

Is this the only debate?

Another one is scheduled for Sept. 10 on ABC.