Tennis is a racket sport that is played either individually against a single opponent (singles) or between two teams of two players each (doubles). Each player uses a tennis racket that is strung with cord to strike a hollow rubber ball covered with felt over or around a net and into the opponent’s court. The object of the game is to manoeuvre the ball in such a way that the opponent is not able to play a valid return. The player who is unable to return the ball validly will not gain a point, while the opposite player will.
Tennis is an Olympic sport and is played at all levels of society and at all ages. The sport can be played by anyone who can hold a racket, including wheelchair users.
A recent addition to professional tennis has been the adoption of electronic review technology coupled with a point-challenge system, which allows a player to contest the line call of a point, a system known as Hawk-Eye.
Tennis is played by millions of recreational players and is a popular worldwide spectator sport. The four Grand Slam tournaments (also referred to as the majors) are especially popular: the Australian Open, played on hardcourts; the French Open, played on red clay courts; Wimbledon, played on grass courts; and the US Open, also played on hardcourts. Wikipedia