The word "sitcom" is short for "situational comedy," and refers to a genre of comedy television which always features the same cast of characters in pretty much the same setting. The setting is usually one of mundanity, meant to offer audiences a more comedic take on work, school, or family environments, for a slice-of-life experience with a little bit of extra humour. Sitcoms usually last a long time because they're relatively cheap to make and generally successful, which means they also come at about a dime a dozen.