<Tr> <Th_colspan="2"> Presence </Th> </Tr> <Tr> <Th> Olympic </Th> <Td> 1964 </Td> </Tr> <P> Volleyball is a team sport in which two teams of six players are separated by a net . Each team tries to score points by grounding a ball on the other team's court under organized rules . It has been a part of the official program of the Summer Olympic Games since 1964 . </P> <P> The complete rules are extensive, but simply, play proceeds as follows: a player on one of the teams begins a' rally' by serving the ball (tossing or releasing it and then hitting it with a hand or arm), from behind the back boundary line of the court, over the net, and into the receiving team's court . The receiving team must not let the ball be grounded within their court . The team may touch the ball up to 3 times but individual players may not touch the ball twice consecutively . Typically, the first two touches are used to set up for an attack, an attempt to direct the ball back over the net in such a way that the serving team is unable to prevent it from being grounded in their court . </P>

How many players are there in volly ball
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