Tennis

Tennis is a sport usually played between two players (singles) or between two teams of two players each (doubles). Each player uses a racquet that is strung to strike a hollow rubber ball covered with felt over a net into the opponent's court.

The modern game of tennis originates in the United Kingdom in the late 19th century as lawn tennis which has heavy relatives to various field or lawn games as well as to the ancient game of real tennis. After its creation, tennis spread all through the upper-class English-speaking population before spreading around the world. Tennis is an Olympic sport and is played at all levels of society at all ages. The sport can be played by someone who can hold a racket, including people wheelchairs.

The rules of tennis have not changed a great deal since the 1890s. Two exceptions are that from 1908 to 1960 the server had to keep one foot on the ground at all times, and then the adoption of the tie-break in the 1970s.

A recent adding up to professional tennis has been the adoption of electronic review technology coupled with a point challenge system, which allows a player to challenge the line (or chair) umpire's call of a point. Players have unlimited opportunity to challenge, but once three incorrect challenges are made in a set, they cannot challenge again until the next set. If the set goes to a tie break, players are given one additional occasion to challenge the call.

This electronic review, currently called Hawk-Eye, is available at a limited number of high-level ATP tournaments. Tennis is enjoyed by millions of recreational dramatis personae and is also a hugely popular worldwide spectator sport, especially the four Grand Slam tournaments (also referred to as the "Majors"): the Australian Open played on hard courts, the French Open played on red clay courts, Wimbledon played on grass courts, and the US Open played also on hard courts.