5.1 A rally is the period during which the ball is in play.
The ball is in play from the last moment at which it is stationary on the palm of the free hand before being intentionally projected in service until it touches anything other than the playing surface, the net assembly, the racquet held in the racquet hand or the racquet hand below the wrist, or until the rally is otherwise decided a let or a point.
5.3 A let is a rally of which the result is not scored.
5.4 A point is a rally of which the result is scored.
5.5 The racquet hand is the hand carrying the racquet.
5.6 The free hand is the hand not carrying the racquet.
5.7 A player strikes the ball if he touches it in play with his racquet, held in the racquet hand, or with his racquet hand below the wrist.
5.8 A player obstructs the ball if he or anything he wears or carries, touches it in play when it is traveling toward the playing surface and has not passed beyond the end line, not having touched his court since last being struck by his opponent.
5.9 The server is the player due to strike the ball first in a rally.
5.10 The receiver is the player due to strike the ball second in a rally.
5.11 The umpire is the person appointed to decide the results of each rally.
5.12 The assistant umpire is the person appointed to assist the umpire. The stroke counter is the person appointed to count strokes under the expedite system.
5.13 Anything that a player wears or carries includes anything that he was wearing or carrying at the start of the rally.
5.14 The ball shall be regarded as passing over or around the net assembly if it passes under or outside the projection of the net assembly outside the table.