Four officials oversee a volleyball game, in addition to an official scorekeeper. The main referee takes an elevated position along the net opposite the teams' benches and the score table. A second referee is positioned on the floor at the net, directly in front of the score table. Two line officials take positions at corners of the court, diagonal from each other, to assist in making calls regarding the landing of the ball inside or outside the lines. The officials control the game by enforcing the rules and use hand signals to indicate most of the calls they make.
Volleyball officials monitor the boundary lines on the court, calling balls in or out depending on where they strike the court. The line officials are usually the first to make the call, but the main referee at the net is able to overrule line calls. Two hands extended forward at about waist height with the palms facing down toward the court indicate that a ball is inside the line. Two arms extended straight up over the head with the palms of the hands facing backward indicate that the ball is out.
The main referee indicates when a point is concluded and to whom the point is awarded. After blowing her whistle, she will point with one hand at the court on the side of the net where the ball hit the floor. This signals the end of that point. She then extends her arm and points to the service line of the team that won that point--using her arm that corresponds to that side of the court--indicating that it has earned control of the serve for the next point.
Player in the Net
Volleyball players must not break the plane of the net by either making contact with the net or stepping beyond the center line on the court. When a player violates this rule, the point is awarded to the other team. The referee will tap the net with an open hand on the side of the net on which the violation occurred to acknowledge the call.
The player serving the ball cannot initiate play until instructed to do so by the main net referee. The official signals the player to serve by extending his arm in the direction of the server with is palm facing up. After blowing the whistle, he then moves his hand in a sweeping direction over his head toward the other side of the net.
Volleyball matches are broken into games. The usual match is played in a best-three-of-five format in which the match ends when one team wins three games. The first four games of a match are played to 25 points. When one team reaches 25, it must be leading by at least two points to capture the game. Once that occurs, the main official indicates that the game is over by crossing her arms across her chest. She then indicates that the two teams switch ends of the court for the next game by passing one arm across the front of her body at waist height, and the other arm across her back at waist height. If a best-of-five match goes to a fifth game, the teams do not switch ends for the fifth game, and that game is played to 15 points instead of 25.