The tennis field is 22m long and 11m wide: In the middle, there is a net.

In general, you need to try, not to let the ball touch the ground. If it does, the other person or team gets a point. The points are counted in a difficult way. If you have 5 points and the others are with two points behind, you get an “ultimate point”. It is counted like this: 5 - 10 – 15 - 30 - 40 – 1 point. Normally you play until 5 points are reached. If the ball hits the outside, the team, which didn’t get it out, gets a point.
Then there are two types of games: Single and double. In a single game the players just use the internal field.
In a double, the whole field is used. After every point, which go made the players change their positions.
I really like the game: I even play it. It is interesting and fast, which makes it really much fun.
Sources: All pictures are downloaded from Wikipedia.