Coaching is Considered to be Communication, Advice or Instruction of Any Kind and by Any Means to a Player.
In team events where there is a team captain sitting on-court, the team captain may coach the player(s) during a set break and when the players change ends at the end of a game, but not when the players change ends after the first game of each set and not during a tie-break game. In all other matches, coaching is not allowed.
Is a player allowed to be coached, if the coaching is given by signals in a discreet way? No.
Is a player allowed to receive coaching when play is suspended? Yes.
Is a player allowed to receive on-court coaching during a match? Sanctioning bodies may apply to have on-court coaching allowed. In events where on-court coaching is allowed, designated coaches may enter the court and coach their players under procedures decided by the sanctioning body.