The premise of roulette is simple: the wheel spins, and if the ball hits a numbered puddle covered by your bet, you win. There are two main versions of the game. The wheel of the American version has 38 pockets (numbers 1-36, plus 0 and 00). In the European version, there are only 37 pockets (numbers 1-36 plus 0). Since there is one less pocket in the European wheel, you have a slightly better chance of winning if you play European roulette.