Tennis is a racket sport played inside a tennis court. As with any sports, when a player wins a point the score is kept but tennis has a unique way of counting scores. Please refer basics of tennis for gaming rules of tennis including serving and turns . Before we discuss tennis scoring, we need to understand points, games, and sets.
A tennis match is made up of sets, and each match is played an odd number of sets and a player (or team) with most winning set wins the match. Most tennis matches are generally played 3 sets, and a player winning 2 sets wins the match (best 2-out-of-3 sets). Men's professional matches in Davis Cup and Grand Slam play best 3-of-5 set matches. In some matches, if players tie at a 1-1 set score, a tie break (7-point) or a match tiebreak (10-points) is played to decide the winner instead of playing a full third set.
A set is made of games, and a player must win six games with at least two game lead to win a set. If the set score becomes 6-5, a winning player must earn another game to win the set. If a set is tied at 6-6, a 7-point tie break is played. As with game scores, a tiebreak must be won by 2-point lead. If a tiebreak is at 7-6, the game continues until one player wins by 2-points. A tiebreak is also considered as a game in the overall scoring scheme, so if a player wins the tiebreak the score becomes 7 games to 6 (or 7-6).
Now we get into an interesting part scoring a game: earning points (plays) and scoring a game. Tennis uses a buzzword, Love, to count zero. For the sake of simplicity, let's call assume a winner of a single play wins a point. In tennis, however, points are not used to score a game. Instead, a score is counted from Love (0), 15, 30, and 40. To win a game, you must win an additional point at 40 and win by 2-points. In tennis, Love is used to count zero. Before each play, it's an etiquette for the server to announce the points earned to eliminate confusion while playing and the server's point is announced first. If the server won 2 plays, and the returner won 0 play, the score becomes 30-Love. In a standard tennis game, a player must win by 2-plays to win a game. If the score is tied at 40-30, and a returner earns a point, the score becomes 40-40 (or "deuce"). From, this point onward each point earned is announced as an "advantage", and Ad-In if the server is at a 1-point advantage and Ad-Out if returner is at a 1-point advantage. The game is continued to play until one player wins by 2-points (or plays).
On some time-limiting matches, No-Ad scoring may be played in games, in which case a 1-point lead will win the game. For example, a score at 40-40, whoever wins the next point wins the game. In No-Ad games, the receiver has a choice to decide the side of play (Ad-side or Duece-side).