This player is the one wearing the different colored jersey and can be substituted in for any player in the back row. The libero cannot rotate into the front row. The addition of the libero has added an extra dimension of back row defense, improved serve-receive, helped lengthen rallies, and given a vital role to shorter players.
Teams score a point on every rally, no matter which team is serving. Back in the day, a team could only score a point if they were serving.
Winning the serve back from the opponent is called a side-out.
Matches are played best of 5 sets. The first four sets got to 25, the fifth set goes to 15. The first team to win 3 sets wins. A team must win a set by two points. The set continues until one of the teams reaches a two point advantage.
Only the three players by the net are allowed to jump, hit, or block by the net. Players in the back row are only allowed to hit if they jump behind the 10-foot line. If their foot crosses that line, it is a back row attack and the other team wins the point.
(10 foot line – the line that separates the front and back part of the court)
There can only be six players on the court, each player must rotate one position clockwise whenever their team wins back service from the opponent.
A team can touch the ball three times on its side of the net. The usual pattern is a dig (an underarm pass made with the forearms), a set (an overhead pass made with the hands), and a spike (the overhead attacking shot). A block is not counted as one of the three touches.