Roullete (French for “little wheel”) is a casino game in which a spinning wheel and ball are used to bet upon which red or black numbered compartment it will land upon as the wheel spins. Originating in late 18th-century casinos of Europe, betting against the casino bank offers lower returns when winning bets come through than losses do.

Probability, or the number of ways an event could possibly take place given its total possible outcomes, forms the mathematical basis for roulette’s math-driven gameplay. Odds of hitting any particular bet can be calculated by multiplying its probability by its total possible outcomes – while various strategies exist for betting on groups rather than individual digits to increase your chances of success when it comes to roulette.

Modern roulette wheels consist of a convex wooden disk which revolves on its axis. At its edge are thirty-six metal partitions known as frets or compartments which have red and black paint; when dropped by croupiers into any one of these compartments a white ball will land into one and spin around until both come to rest on one of three green compartments, which on European tables mark 0, while on American tables there may be two additional green compartments marked 0 and 00.

Before spinning the wheel, players place bets on which number the ball will land by placing chips on a betting mat and precisely placing their chips. The precise placement of chips indicates a bet being made; bets placed on six numbers or less are known as inside bets while bets on 12 or more are known as outside bets.

Roulette balls were once made from ivory; nowadays they’re made of high-grade synthetic material with an ivory aesthetic and feel. Weight and size play an integral role in how roulette works; for instance, lighter ceramic balls make more revolutions on the wheel than their ivorine counterparts.