A tie-break set is played with the same rules as the advantage set, except that when the score is tied at 6–6, a tie-break game (or tiebreaker) is played. Typically, the tie-break game continues until one side has won seven points with a margin of two or more points. However, many tie-break games are played with different tiebreak point requirements, such as 8 or 10 points. Often, a 7-point tie-breaker is played when the set score is tied at 6–6 to determine who wins the set. If the tiebreak score gets to 6-6, then whichever player to win the best of two points wins the set. 
The origin of the use of "love" for zero is also disputed. The most likely explanation is that it derives from the French expression for "the egg" (l'œuf) because an egg looks like the number zero. This is similar to the origin of the term "duck" in cricket, supposedly from "duck's egg", referring to a batsman who has been called out without scoring a run. One possibility comes from the Dutch expression iets voor lof doen, which means to do something for praise, implying no monetary stakes. Another theory on the origins of the use of "love" comes from the notion that, at the start of any match, when scores are at zero, players still have "love for each other".
Throughout most of lawn tennis' history, most rackets were made of laminated wood, with heads of around 65 square inches (420 cm2). A small number of them were made of metal, such as a 1920s racket by Dayton. Some, rarely, also had metal strings. In the late 1960s, Wilson popularized the T-2000 steel racket with wire wound around the frame to make string loops, after having purchased the design from René Lacoste, who produced the racket first in a more limited run. It was popularized by the top American player Jimmy Connors and was also, prior to Connors using it, by Billie Jean King in her early career. Many players said it lacked control but had more power, when compared with wood frames of the period. Connors used the rarer "firm" model that had additional throat welds to increase its stiffness. In 1968 Spalding launched an aluminum racket, called The Smasher. Aluminum, though lighter and more flexible than steel, was sometimes less accurate than wood. The biggest complaint, however, was that metal rackets caused strong cases of tennis elbow, especially the kind that had holes for the strings directly in the frame, rather than using an external wire wrapper, as in the T-2000. Because of that drawback in particular, most of the top players still preferred to use wooden frames.
Tennis is a racket sport that can be played 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 maneuver 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 will not gain a point, while the opposite player will.