Tennis balls are divided into balls and blankets. The balls are made of rubber. The wool content of the game ball felt is very high, while the wool content of the training ball felt is not high. Also, the game ball is full of air pressure. It will run out of gas after playing for a period of time. It is not very durable.

Tennis service should be sent in the following way. The service player shall stand before starting to serve, that is, stand behind the baseline (that is, the side away from the net), within the assumed extension line of the center mark and the sideline. Then the service player should throw the ball in any direction in the air with his hand and hit the ball with his racket before it touches the ground. At the moment when the racket contacts the ball, the whole transmission is considered to have ended. A player who can only use one arm can use his racket for throwing.