Act 1: Johnny Carson’s retirement in 1992 set off a longstanding rivalry—known as the Late Night Wars—between David Letterman and Jay Leno, who was chosen to take over the coveted 'Tonight Show.' Letterman moved to CBS to host the new 'Late Show,' which would compete with 'The Tonight Show' for ratings over the next two decades.

Act 2: Young upstart hosts Jon Stewart, Stephen Colbert and Conan O’Brien begin to pose a threat to late night veterans. Hosting cable shows, however, they never reached the audiences of network TV. Also a substantial portion of their viewership is online. According to Comedy Central, a December 2014 episode of 'The Colbert Report' had 3.6 million online streams—three times his average TV viewership that year.

Act 3: With Colbert taking over 'The Late Show' from Letterman, the upstarts will become the old guard. Already in 2014, Jimmy Fallon took the mic from Leno, marking a new, younger era in 'The Tonight Show.' Meanwhile new faces like Grace Helbig and Larry Wilmore started airing this season, bringing their own brand of comedy to the future of late night.

Next