Short answers, pulled from the story.
David Letterman hosted 6,080 episodes in total across Late Night with David Letterman on NBC and Late Show with David Letterman on CBS, surpassing Johnny Carson as the longest-serving late-night talk show host in American television history.
Late Night with David Letterman premiered on the 1st of February 1982, on NBC. The first guest was Bill Murray, who also appeared on Letterman's final Late Show episode on the 20th of May 2015.
Letterman left NBC for CBS in 1992 after NBC chose Jay Leno over him to succeed Johnny Carson as host of The Tonight Show. CBS signed Letterman to a three-year, $14 million-per-year contract to host Late Show with David Letterman opposite The Tonight Show.
On the 14th of January 2000, a routine checkup revealed a severely obstructed artery, and Letterman was rushed to New York Presbyterian Hospital for emergency quintuple bypass surgery. He returned to the Late Show on the 21st of February 2000, bringing nearly all the doctors and nurses who had treated him onto the stage.
On the 1st of October 2009, Letterman announced he had been the victim of an extortion attempt involving a threat to expose his sexual relationships with female employees unless he paid $2 million. Joe Halderman, a producer for the CBS news magazine 48 Hours, was arrested after trying to deposit a fake check as part of a sting operation, pleaded guilty in March 2010, and was sentenced to six months in prison.
Since retiring in 2015, Letterman has hosted My Next Guest Needs No Introduction with David Letterman on Netflix, which premiered the 12th of January 2018, with Barack Obama as its first guest. The series has included interviews with Barack Obama, Kim Kardashian West, Billie Eilish, and Ukrainian president Volodymyr Zelenskyy, filmed in Kyiv in October 2022. Season 6 premiered on the 16th of December 2025.