What is Roulette?

Roulette is among the most recognisable casino games. A wheel of numbered pockets spins one way while a ball is sent around the rim the other way, and where the ball settles decides the result. Players can bet on a single number, on colours such as red or black, or on groupings like odd or even and high or low, with payouts scaled to how many numbers each bet covers. The house edge is fixed entirely by the wheel's design. A European wheel carries 37 pockets, numbered 0 to 36 with a single green zero, giving a house edge of 2.70%. An American wheel adds a second green pocket, the double zero, for 38 pockets and a house edge of 5.26%. The payouts are identical on both wheels, so the extra zero is the sole reason the American game costs the player almost twice as much over time. A worked example shows where the edge hides. A straight-up bet on one number pays 35 to 1, yet on a European wheel there are 37 possible results, so the true odds against you are 36 to 1; that one-pocket shortfall is exactly the house margin. French roulette softens the blow on even-money bets through the la partage and en prison rules, which return or hold half the stake when zero lands, cutting that edge to about 1.35%. The enduring mistake is believing a betting system can beat the wheel. Doubling after a loss may produce frequent small wins but exposes the player to catastrophic losing streaks and table limits, and cannot change the per-spin edge. Each spin is independent, so prefer single-zero wheels and treat roulette as entertainment with a known cost rather than a solvable puzzle.