Overtime in hockey results when the game ends in a tie after three periods of play. Overtime in the NHL is played in a "sudden death" fashion, meaning that the first team to score in overtime wins the game. Overtime consists of a single five-minute period played with four players on each team.
If no one scores in overtime, the NHL mandates the game go to a shootout. The winner of the shootout is considered the winner of the game. In the Stanley Cup playoffs, there are no shootouts, and overtime consists of a full twenty-minute period of five-on-five hockey. These overtime periods are played in sudden death fashion as well, with the first goal winning the game. During the playoffs, there is no limit as to how many overtime periods can be played before the game ends. There are also no commercial breaks, or TV time-outs, during playoff hockey overtime.