Rally
A rally is won when a shuttle is hit over the net and onto the floor of the opponent's court.

A rally is lost if the shuttle is hit into the net, or over the net but outside of the opponent's court. A rally is also lost if the shuttle touches the player's clothing or body, or if it is hit before it crosses over the net.

Serving
The service courts are slightly different for singles and doubles. A shuttle on the line is "in". The server and receiver stand in the diagonally opposite service courts (always right hand at the start of the game) but therefore players may move anywhere on their side of the net. The server must obey laws designed to force underhand delivery of the serve, and the receiver must stand still until the service is struck.

Scoring
Matches comprise of the best of three games. Each game starts at 0-0 (traditionally called "love-all").

Classic scoring Format
If the serving side wins a rally, it scores a point, and serves again but from the alternate service court. If the receiving side wins the rally, the score remains unchanged and the service passes to the next player in turn. In singles, this is the opponent: in double it's either the partner or, if both players have just had a turn of serving, one of the opponents.

In men's singles and doubles events, 15 points wins a game. However, if the score reaches 14-14, the side which first reached 14 can choose either to play to 15, or to set the game to 17 points. The final score will reflect the sum of the points won before setting plus the points gained in setting.

Scoring in women's singles is slightly different. 11 points wins a game and there is the option to set to 13 points at 10-10.

And Finally...
Players change ends at the end of a game and when the leading score reaches 8 in a game of 15 points (or 6 in a game of 11 points) in the third game. A five minute interval is allowed prior to any third game.