How many periods are in an ice hockey game?

In ice hockey, a standard game consists of three periods. Each period typically lasts 20 minutes of played time, making a total of 60 minutes not including stoppages for various reasons such as penalties, goals, or injuries. The structure of having three periods is a key feature of the game, allowing for intermissions between each period where teams can regroup and strategize. This format is consistent across professional leagues, including the NHL and international competitions.