From The TV IV

The Tonight Show is a late night talk show franchise that airs on NBC. There were three versions of the show under varying names before The Tonight Show become the official moniker. Since then, there have so far been two shows, with host Johnny Carson and Jay Leno, and the third iteration will start June 1, 2009 with Conan O'Brien.

Title	Format	Network	Years	Notes
Tonight	Talk show	NBC	1954–57	Hosted by Steve Allen
Tonight! America After Dark	Talk show	NBC	1957
Tonight Starring Jack Paar	Talk show	NBC	1957–62	Renamed for part of its run as The Jack Paar Show
The Tonight Show Starring Johnny Carson	Talk show	NBC	1962–1992
The Tonight Show with Jay Leno	Talk show	NBC	1992–2009
The Tonight Show with Conan O'Brien	Talk show	NBC	2009–