Saturday Night Live (abbreviated as SNL) is an American late-night live television sketch comedy and variety show created by Lorne Michaels and developed by Dick Ebersol. The show premiered on NBC on October 11, 1975, under the original title NBC's Saturday Night. The show's comedy sketches, which parody contemporary culture and politics, are performed by a large and varying cast of repertory and newer cast members. Each episode is hosted by a celebrity guest (who usually delivers an opening monologue and performs in sketches with the cast) and features performances by a musical guest. An episode normally begins with a cold open sketch that ends with someone breaking character and proclaiming, "Live from New York, it's Saturday Night!", properly beginning the show.

In 1980 Michaels left the series to explore other opportunities. He was replaced by Jean Doumanian, who was replaced by Ebersol after a season of bad reviews. Ebersol ran the show until 1985, when Michaels returned; Michaels has remained since then. Many of SNL's cast found national stardom while appearing on the show, and achieved success in film and television, both in front of and behind the camera. Others associated with the show, such as writers, have gone on to successful careers creating, writing, or starring in TV and film.

Broadcast from Studio 8H at NBC's headquarters in the Comcast Building, SNL has aired 800 episodes since its debut, and began its forty-first season on October 3, 2015, making it one of the longest-running network television programs in the United States. The show format has been developed and recreated in several countries, including Canada, Spain, Italy, South Korea, Japan, Brazil, and Finland, each meeting with different levels of success. Successful sketches have seen life outside of the show as feature films, although only two met with critical and financial success: The Blues Brothers (1980) and Wayne's World (1992). The show has been marketed in other ways, including home media releases of "best of" and whole seasons, and books and documentaries about behind-the-scenes activities of running and developing the show.

Throughout four decades on air, Saturday Night Live has received a number of awards, including 42 Primetime Emmy Awards, two Peabody Awards, and three Writers Guild of America Awards. In 2000, it was inducted into the National Association of Broadcasters Hall of Fame. It was ranked tenth in TV Guide's "50 Greatest TV Shows of All Time" list, and in 2007 it was listed as one of Time magazine's "100 Best TV Shows of All-TIME". As of 2012, it has received 156 Emmy nominations, the most received by any TV show. The live aspect of the show has resulted in several controversies and acts of censorship, with mistakes and intentional acts of sabotage by performers as well as guests.