he first season of Saturday Night Live, the weekly late-night 90-minute American sketch comedy/variety show on NBC, aired during the 1975–1976 television season. Saturday Night Live premiered on October 11, 1975 and consisted of a total of 24 episodes, the last of which aired on July 31, 1976.

In 1974, NBC Tonight Show host Johnny Carson requested that the weekend broadcasts of "Best of Carson" come to an end, so that Carson could take two weeknights off and NBC would thus air those repeats on those nights rather than feed them to affiliates for broadcast on either Saturdays or Sundays. Given Carson's undisputed status as the dean of late-night television, NBC heard his request as an ultimatum, fearing he might use the issue as grounds to defect to either ABC or CBS. To fill the gap, the network drew up some ideas and brought in Dick Ebersol – a protégé of legendary ABC Sports president Roone Arledge – to develop a 90-minute late-night variety show. Ebersol's first order of business was hiring a young Canadian producer named Lorne Michaels to be the show-runner.

Overview from themoviedb.org