A foot fault in volleyball occurs when a players foot touches the court outside their designated playing area during their attack or serve. Foot faults can occur during any service attempt or during normal play. There are two types of foot fault penalties in volleyball, which are judged whenever a player on one team steps beyond a boundary line with any part of their foot. The first form of foot fault is a foot fault committed during a serve. When serving the ball to the opposing team, the volleyball player who is positioned at the rear-right side of their team’s territory must step back into the service zone, just behind the end line, before serving the ball. If the servers foot touches anything adjacent to the baseline or the imaginary extension of the center mark, it could be a foot fault. The second type of foot fault that can occur in volleyball is a foot fault over the centerline. During play, any player whose foot crosses beneath the net commits a foot fault.

In summary, a foot fault in volleyball is when a players foot touches the court outside their designated playing area during their attack or serve. There are two types of foot fault penalties in volleyball, which are judged whenever a player on one team steps beyond a boundary line with any part of their foot.