Roullete is a game of chance in which a small ball is dropped into a spinning wheel and players make wagers on which red or black numbered compartment it will come to rest in. Various combinations of bets pay off at higher odds than others, but the player’s total bet is always the same.
The roulette wheel is a revolving dishlike device consisting of a disc with 37 or 38 compartments, alternately red and black, with a single zero or double zero (European wheel) or one green and two red (American wheel). The rotor is balanced by its spindle so that the bouncing of the ball is almost frictionless. A croupier, or dealer, is in charge of the game.
Before the croupier spins the wheel, the players make their bets. The croupier then releases the ball into the wheel. The ball will bounce around the wheel until it comes to rest in one of the compartments, revealing whether there are winners who have bet on specific numbers or groups of numbers, on colors or on high-low, odd-even, first, second and third dozen or columns.
The payouts for winning bets are indicated on the table. A straight bet on number 17 costs 40 chips, and pays 392 chips if it wins. The symmetry of the roulette layout allows for some interesting calculations. For example, a pair of neighbors, number 1 and 2, cost 19 chips and pay 297 chips. The three-number symmetries are also interesting. Interestingly, the sequence 29-7-28-12-35-3-26-0-32 contains no low red or high black numbers, and therefore no second or third dozen bets (which pay at 2-1). The symmetry of the number groupings on the American wheel is less clear.