In tennis, a "set" is defined as a portion of the match where a player must win a predefined number of games—typically six—by at least a two-game margin to claim the set. If the players reach a 6-6 tie in games, a tiebreak may occur to determine the winner. Sets are crucial in tennis, as matches are played in a best-of-three or best-of-five sets format, with the overall winner being the first to win the majority of sets.