Stefanie Maria Graf is a German former professional tennis player. She won 22 major singles titles, the second-most in women's singles won since the start of the Open Era in 1968 and the third-most of all-time. In 1988, Graf became the first tennis player to achieve the Golden Slam by winning all four major singles titles and the Olympic gold medal in the same calendar year. She is the only tennis player, male or female, to have won each major singles tournament at least four times.

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.