David Michael Letterman (born April 12, 1947) is an American television host, comedian, writer, producer, and actor. He hosts the late night television talk show Late Show with David Letterman, broadcast on CBS. Letterman has been a fixture on late night television since the February 1, 1982 debut of Late Night with David Letterman on NBC. In 1996, David Letterman was ranked #45 on TV Guide 's 50 Greatest TV Stars of All Time. In 2013, Letterman surpassed friend and mentor Johnny Carson as the longest-serving late night talk show host in TV history, at 31 years. On April 3, 2014, Letterman announced he would retire in 2015. He will host the Late Show for the last time on May 20, 2015. CBS announced that Stephen Colbert, comedian, writer and host of Comedy Central's The Colbert Report since 2005, will take his place.