Late-night talk show

A late-night talk show is a genre of talk show popular in the United States, where the format originated. It is generally structured around humorous monologues about the day's news, guest interviews, comedy sketches and music performances. The late-night talk show format was popularized, though not invented, by Johnny Carson with The Tonight Show Starring Johnny Carson on NBC. Typically the show's host conducts interviews from behind a desk, while the guest is seated on a couch. Many late night talk shows feature a house band which generally performs cover songs for the studio audience during commercial breaks and occasionally will back up a guest artist.

Late-night talk shows are a popular format in the United States, but are not as prominent in other parts of the world. Shows that loosely resemble the format air in other countries, but generally air weekly as opposed to the nightly airings of those in the United States. They also generally air in time slots considered to be prime time in the United States.

Late-night talk shows had their genesis in early variety shows, a format that migrated to television from radio, where it had been the dominant form of light entertainment during most of the old-time radio era. Early television variety shows included The Ed Sullivan Show (originally known as Toast of the Town), which aired on CBS Sunday nights from 1948 to 1971 and was hosted by Ed Sullivan, and Texaco Star Theater with Milton Berle, which aired on NBC from 1948 to 1956. These shows aired once a week in evening time slots that would come to be known as prime time. The first show to air in a late night time slot itself, Broadway Open House, aired on NBC in 1950 and ended a year later after host Jerry Lester left the show, infuriated at being upstaged by his sidekick Virginia "Dagmar" Lewis. (As it was, there were also not yet enough television sets in the United States to make television broadcasting in late-night viable.) The first version of The Tonight Show, Tonight Starring Steve Allen, debuted in 1954 on NBC. The show created many modern talk show staples included an opening monologue, celebrity interviews, audience participation, comedy bits, and musical performances. By this point, the Federal Communications Commission had lifted a freeze on new television stations, which allowed new stations to pop up across the country, and television adoption soon grew exponentially. As a result, unlike Broadway Open House, Tonight proved to be a resounding success.

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