A situation comedy, or sitcom, is a genre of comedy centered on characters who share a common environment, such as a home or workplace, with often-humorous dialogue. Sitcoms originated in radio, but today are found mostly on television as one of its dominant narrative forms. This form can also include mockumentaries. A situation comedy television program may be recorded in front of a studio audience, depending on the program's production format. The effect of a live studio audience can be imitated or enhanced by the use of a laugh track.