Table tennis (also called ping pong) is a sport in which two or four players hit a lightweight ball back and forth using a table tennis bat. The game takes place on a hard table divided by a net. Except for the initial serve, players must allow a ball played toward them only one bounce on their side of the table and must return it so that it bounces on the opposite side. Points are scored when a player fails to return the ball within the rules. Play is fast and demands quick reactions. Spinning the ball alters its trajectory and limits an opponent's options, giving the hitter a great advantage. When doing so the hitter has a good chance of scoring if the spin is successful.