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Leno Makes His Debut (May 25, 1992)
Three days after Johnny Carson retired, Leno took over hosting duties at The Tonight Show. Though many people (including Carson himself) preferred David Letterman to be the new host, Leno — who had made several appearances on The Tonight Show as a guest host and stand-up comedian — was selected. Comedian Billy Crystal, Leno's first guest, came full circle and also appeared on Leno's final episode on Feb. 6, 2014.