The rules of tennis have not changed for centuries. Stripped of its special rules for serving and chases, the game is simple to understand. Each player strives to get the ball over the net and in doing so may use any wall - as in squash. The scoring is the same as in lawn tennis (15, 30, 40, deuce, advantage), except that the score of the winner of the last point, and not that of the server, is called first.
A set is won by the first player to win 6 games. So, if the score is five games all, there is a final deciding game. At the conclusion of each game the winner of that game has his score called first. As in lawn tennis singles or doubles can be played. The length of the Royal Tennis Court is approximately one and a half times the length of a lawn tennis court: its width a fraction more than the width of a doubles Lawn Tennis Court. Halfway between the two ends a net stretches from side to side of the court. In the centre the height of the net is the same as a Lawn Tennis net. At either end the net is higher, in fact, five foot.
Various features of a tennis court are still known by their original French names. Thus the long opening at the end of the service side of the court (behind which spectators can sit and watch a game) is known as the "Dedans". At the opposite end of the court the buttress projecting from the wall is known as the "tambour" and the wooden opening near it is called the "grille". These details are shown on the Court Plan.
A game is begun by a service which is always from the same end of the court (the service side). The opposite end of the court where the receiver stands is called the hazard side. The service does not alternate with each game as in lawn tennis. The server changes ends and ceases to serve only when a chase has been laid. The meaning of a chase will be explained below. To be a good service the ball has to touch the penthouse roof at least once on the hazard side of the net and drop in the service court. If it does not touch the penthouse roof or if it hits a window or the roof it will be a fault.
A chase is laid where the ball bounces the second time without being hit by the player. On the service side a chase is laid wherever the ball bounces a second time. On the hazard side a hazard chase is laid if the ball bounces the second time between the net and the line parallel to it furthest from the net. If it lands a second time between that line and the back wall, it is a point for the server.
The galleries on either side of the net also count as chases, with the exception, on the hazard side of the winning gallery. If the ball enters the winning gallery, it is a point for the server. Other winning openings which provide outright winners are the dedans on the service side and the grille on the hazard side.
If a chase is laid, the point is not won by that shot, the point is kept in abeyance until the player changes ends. When the players change end, the receiver (who was previously the server) has to beat the chase. The players change ends if two chases have been laid or if one player reaches game point and there is one chase. If it is a hazard chase, the receiver will beat the chase by playing any shot which the server cannot return, either on the floor or by hitting one of the galleries on the service side. If it is a service chase, the receiver will beat the chase by the second bounce landing nearer the back wall than the chase. To assist in determining where precisely a ball bounces the second time, lines are marked on the floor at intervals of one yard. The figures above the lines on the opposite wall show the number of yards measured, on the service side, from the back wall and, on the hazard side, from the service line. The nearer a chase on the service side is to the back wall, the more difficult it is to beat.
When the players change ends, the first point to be played is the chase. The marker will call out the chase which the receiver hopes to beat. If the chase is exactly on a yard line, the marker will call out the number of yards, e.g. "chase 2 and 3" means two and a half yards from the back wall. If the chase falls between a yard and a half-yard line, the marker will call out "better than" or "worse than" the yard line, depending on whether the ball fell nearer the back wall, or further from the back wall, than the yard line. If the ball went into a gallery, the marker calls out the name of that gallery, e.g. the Last Gallery. Each gallery has a line on the floor opposite to the centre of the gallery. If the chase is laid on the floor between galleries, the marker calls out "better / worse than" say, the Second Gallery.