The procedure prior to kickoff that determines which team will receive the ball, and which end zone each team will defend. The visiting team will call the coin toss in the air after the official flips the coin, and whichever team wins the toss will get to either choose kicking off, receiving, or choosing an end zone to defend. The captains from each team are usually representative for the kickoff. For some games, a special coin is used.
The coin toss precedes each game, and each team will have a different strategy for what to do if they win the toss. Some teams prefer to start with the ball right away, while others will kickoff to give themselves the ball after halftime. Usually, a team will only choose to defend a particular end zone when there are adverse conditions, such as wind, that give a significant advantage to going a particular direction. The visiting team always makes the call on a coin toss.