A doubleheader is a term used by television networks to refer to two games involving the same sport that are shown back-to-back on the same network, even though the events do not involve the same two teams (three such games may be referred to as a tripleheader, this scenario occurring most frequently in regard to basketball). A doubleheader purposely coincides with a league's scheduling of "early" and "late" games. In North America, games usually start at the same time period in different time zones (Eastern and Pacific).