Twitter mentioned Donald Trump nearly two times for every time Hillary Clinton was mentioned by the end of the debate, which the social media company said was the most tweeted debate ever.
In a series of tweets Sen. Elizabeth Warren of Massachusetts called Trump a "thin-skinned bully" and characterized his performance as that of a "man who was ranting & raving on stage."
@elizabethforma: .@realDonaldTrump proved once again tonight: He's a thin-skinned bully who doesn't care about anyone but himself. #debatenight
@elizabethforma: .@realDonaldTrump's economic plan? Cut taxes for billionaires & the rules on Wall Street, & leave working families behind. #debatenight
@elizabethforma: The man who was ranting & raving on stage tonight has no business controlling our economy OR our nuclear codes. #debatenight
Reince Priebus, chairman of the Republican National Committee, criticized Clinton during the debate and said she isn't trustworthy
@Reince: Why should we trust Clinton with our nation's cybersecurity when she so recklessly jeopardized classified information? #Debates2016
The wordsmiths at Merriam-Webster joined in on the fun with a nod toward Trump's unique use of the word "bigly."
The word "stamina" became a buzzword later in the debate, spurring a flood of tweets.
And 400-pound hackers became another theme on social media.
Before the debate began, Dallas Mavericks owner Mark Cuban tweeted a photo of his front-row seat number.
Former President Bill Clinton tweeted that he is "looking forward to tonight's debate knowing that millions of Americans" will get to know the Hillary Clinton that he has known for more than 40 years.
@billclinton: Looking forward to tonight's debate knowing that millions of Americans will see the @HillaryClinton I've known for over 40 years.
Sen. Bernie Sanders emphasized that the candidates should focus on the issues and not treat the debate as an "entertainment show."
@BernieSanders: What we have to do is focus on the issues, not see tonight as an entertainment show. #debatetonight
—CNBC's Michael Newberg contributed to this report.