LIVE: @NBCNewsNow looks ahead to tonight's first presidential debate between President Trump and Biden. #Debates2020

It's the first time the two candidates will face off on the debate stage after months of tweets and attack ads.

It's the first time the two candidates will face off on the debate stage after months of tweets and attack ads.

Track what President Donald Trump and Joe Biden talk about, and how much they stay on-topic, at tonight’s debate.

As the two candidates cover six topics ranging from the Supreme Court to Covid-19, NBC News will provide live fact checking during the debate.

Fact check: Trump says the GOP protects people with pre-existing conditions

Fact check: How many people are there in the U.S. with pre-existing conditions?

It's the first time the two candidates will face off on the debate stage after months of tweets and attack ads.

It's the first time the two candidates will face off on the debate stage after months of tweets and attack ads.

It's the first time the two candidates will face off on the debate stage after months of tweets and attack ads.

It's the first time the two candidates will face off on the debate stage after months of tweets and attack ads.