100. David Letterman: Late Night Comedy

Late night talk show host David Letterman is known as the king of late night for his dry humor and impeccable timing. He has been hosting the show that bears his name since 1993 after he was passed over for Johnny Carson's replacement following the 1992 season. Many observers felt Letterman was the obvious choice to replace Carson when the latter retired. "Late Night with David Letterman" had the choice time slot immediately following Carson, and both were under contract with the National Broadcasting Company (NBC).

"The Late Show with David Letterman" debuted on August 30,1993. Letterman took his fan base with him to CBS for the most part, and the battle lines had been drawn. Letterman's new show of his show on NBC. CBS executives did not want Letterman to import his old show, opting to create a new image for Letterman. Letterman persisted and his show took root, and found its audience. Letterman has since surpassed Carson's record for longevity in 2013. Letterman has now hosted a late night show for more than 31 years.

Letterman's early life was influenced by his father, who was also a comic. He was born in Indianapolis, Indiana on April 12, 1947. His first foray into the entertainment industry came while a college student at Ball State University, where he served as a radio broadcaster for the student-run station. He moved to Los Angeles in 1975 at the behest of his former wife. Once in L.A., Letterman began doing stand-up comedy, at the world famous Comedy Club, and his career was launched.