What is "laugh track"

n. The soundtrack of laughter sounds that accompanies a television comedy show

n. prerecorded laughter added to the soundtrack of a radio or television show

A laugh track (or laughter track) is a separate soundtrack for a recorded comedy show containing the sound of audience laughter. In some productions, the laughter is a live audience response instead; in the U.S., where it was most used, the term usually implies artificial laughter (canned laughter or fake laughter) made to be inserted into the show. This was invented by American sound engineer Charles "Charley" Douglass.

The Douglass laugh track became a standard in mainstream television in the U.S., dominating most prime-time sitcoms from the late 1950s to the late 1970s. By the 1980s, the Douglass family was eventually outrivalled by other sound engineers who created stereophonic laugh tracks different from the original analog track. Also, many single-camera sitcoms by this time started diverting from a laugh track altogether to create a more dramatic environment.