Wheelchair tennis is a sport adapted from traditional tennis, allowing players with physical disabilities to compete in singles or doubles matches. The main difference is that players are allowed to use a wheelchair and the ball can bounce twice before being returned, with the first bounce allowed outside the court lines. The sport is governed by the International Tennis Federation (ITF) and follows similar rules to able-bodied tennis, with some modifications. Wheelchair tennis is played on various surfaces, including grass, clay, and hard courts, and is included in major tournaments like the Grand Slam events.