Jay Leno began hosting NBC's long-running late night program The Tonight Show in 1992. Leno was already famous as a standup comedian with intense work habits; he reportedly toured 300 nights a year during the late 1980s. He eventually became a regular vacation standin for Johnny Carson, who hosted The Tonight Show for nearly 30 years. When Carson retired in 1992, Leno got the job full-time. (The same job had been coveted by comedian David Letterman, whose own program had followed Carson's for years. Letterman then moved his program Late Night to CBS, beginning a long-running rivalry between his program and Leno's.) Leno is known as a collector of automobiles and motorcycles, and is often kidded about having an oversized chin. (His book Leading With My Chin was published in 1998.) In 2004 he signed a contract extension to continue hosting The Tonight Show through 2009. The same year, NBC announced that Leno would step down as the host of The Tonight Show in 2009, to be replaced by Conan O'Brien.

Leno married his wife Mavis in 1980; they have no children.

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