Rowan & Martin's Laugh-In was an American sketch comedy television program which ran for 140 episodes from January 22, 1968 to May 14, 1973. It was hosted by comedians Dan Rowan and Dick Martin and was broadcast over NBC. It originally aired as a one-time special on September 9, 1967 and was such a success that it was brought back as a series, replacing The Man from U.N.C.L.E. on Mondays at 8pm on NBC.
The title, Laugh-In, came out of events of the 1960s hippie culture, such as "love-ins" or "be-ins." These were terms that were, in turn, derived from "sit-ins," common in protests associated with civil rights and anti-war demonstrations of the time.
The show was characterized by a rapid-fire series of gags and sketches, many of which conveyed sexual innuendo or were politically charged. Rowan and Martin continued the exasperated straight man (Dan Rowan) and "dumb" guy (Dick Martin) act which they had established as nightclub comics.
Laugh-In had its roots in the humor of vaudeville and burlesque, but its most direct influences were from the comedy of Olsen and Johnson (specifically, their free-form Broadway revue Hellzapoppin'), the innovative television works of Ernie Kovacs, and the topical satire of That Was The Week That Was.