A player needs at least 6 games to win a standard tennis set. However, the player must also lead by two games, so a 6–4 score wins the set, while 6–5 does not.
If the score reaches 6–6 in a tiebreak set, a tiebreak usually decides the set, producing a final score of 7–6. In an advantage set, play continues beyond 6–6 until someone establishes a two-game margin, such as 8–6 or 12–10.
A tennis match is built from points, games, and sets. Points make up games; games make up sets; and sets determine the match winner. The familiar scoring sequence inside a game—15, 30, 40, then game—is separate from the running game score in a set.
Six is the minimum in the traditional format, but alternative formats exist. Short sets can be won at four games, while an eight-game pro set uses eight games. Those formats are exceptions rather than the standard set used in major professional tennis.