Actors, comics and musicians took to Twitter, Instagram and Facebook to share congratulations as well as memories from their time on Dave’s show.
Some even shared stories of how Dave influenced their lives and careers. Parks and Recreation star Adam Scott shared, “A good 80% of why I wanted to do any of this was to one day sit on Letterman's couch.”
Some stars didn't want to accept the reality of the situation. Jennifer Lawrence posted a photo begging Letterman not to leave.
Even his fellow late-night hosts encouraged their viewers not to miss his last episode.
Many celebrities just wanted to make it known that they appreciated all the laughs and good times from Letterman's long, groundbreaking career in late-night television.
This truly is the end of an era, and it will be interesting to see how his successor, Stephen Colbert, does behind the "Late Show" desk.