Law & Order is an American police procedural and legal drama television series, created by Dick Wolf and part of the Law & Order franchise. It originally aired on NBC and, in syndication, on various cable networks. Law & Order premiered on September 13, 1990, and completed its 20th and final season on May 24, 2010. At the time of its cancellation, Law & Order was the longest-running crime drama on American primetime television. Its record of 20 seasons is a tie with Gunsmoke (1955–1975) for the longest-running live-action scripted American prime-time series with ongoing characters, although it had fewer episodes than Gunsmoke, but since that series was a half-hour in its first six seasons, Law & Order is the longest-running full-hour series in primetime television.