Relays involve 4 competitors per team, swimming equal distances (100 meters each) one after another in the same lane. Teams compete against each other based on the time period within which teams complete the distance. There are two types of relays: the medley relay, where each swimmer swims a different stroke, and the freestyle relay where all of them swims freestyle. You can choose the type according to the preferences of the participants. Either way, the team whose last member reaches the finish line first wins the competition.
The team, which completes 4x100m within the shortest time period, wins the competition.