Jay Leno and the 'Tonight Show' hosts

Time is winding down for Jay Leno on "The Tonight Show." He is the subject of a CNN special, "Jay Leno: Mr. Comedy," which will air at 10 p.m. ET Friday. Leno will helm his final episode on February 6 before turning over his chair to new host Jimmy Fallon. Here is a look at the history of hosts for the iconic late night talk show.

Johnny Carson's 30 years as a host of "The Tonight Show" made him a talk show icon. Carson, who hosted from 1962 to 1992, set the standard for late night show formats and style. Here, Carson speaks to a guest in 1964.

Comedian and songwriter Steve Allen was the show's first host, from 1954 to 1957. His prolific career earned him two stars on the Hollywood Walk of Fame. Here, Allen poses for a promotional portrait in 1955.

Jack Paar's unpredictable and dramatic presence drew more than 7 million viewers every night between 1957 and 1962. The show was renamed "The Jack Paar Show" while he was host.

Jay Leno starred in "The Tonight Show with Jay Leno" from 1992 to 2009 and then moved to his own prime-time show, "The Jay Leno Show," on NBC. After a public controversy over scheduling changes while Conan O'Brien hosted the show in 2009, Leno returned to host "The Tonight Show" in 2010. Here, Leno jokes with Jerry Seinfeld in 1998.

Conan O'Brien hosted the show for seven months and left after NBC announced that it would be moving his show to after midnight and Leno's prime-time show to "The Tonight Show's" time slot. Here, O'Brien on his final show on January 22, 2010.

Leno returned in March 2010. Here, Leno chats with President Barack Obama in October 2012.

Jimmy Fallon's takeover of "The Tonight Show" has been inevitable, show producer Lorne Michaels told GQ. "He's the closest to (Johnny) Carson that I've seen of this generation," Michaels said. Fallon, who rose to fame as a cast member on "Saturday Night Live" from 1998 to 2004, currently hosts "Late Night with Jimmy Fallon." Here, Fallon chats with Olympic swimmer Ryan Lochte.