Roulette, or Roullete in French, is a casino game involving a spinning wheel and a ball. Players place bets on individual numbers, groups of numbers, the color red or black, whether a number is odd or even, or if the numbers are high (19-36) or low (1-18). A winning bet pays out 35 times the amount staked. Casinos see betting at the table as a source of revenue, and they seek to limit the house edge by banning cheating and other techniques. However, there are still a small number of roulette bets that offer higher win to stake ratios than others.
The game’s wheel consists of a solid wooden disk slightly convex in shape with 36 compartments, or pockets, painted alternately red and black and numbered non-consecutively from 1 to 36. The outer rim of the wheel contains metal separators, or frets, and on American roulette wheels two green compartments on opposite sides of the wheel carry the signs 0 and 00. A single ball, a steel sphere of roughly the size of a golf ball, is spun in a circular direction by a roulette croupier and is dropped into one of the pockets when it stops. The dealer then announces the winning number and collects all losing bets as income for the casino.
Prior to the spin of the roulette ball, players place their chips on a betting mat, with precise placement indicating the type of bet placed. In general, bets on six numbers or less are referred to as Inside bets and bets on 12 numbers or more are called Outside bets. The game also features a rule called “la partage” (in prison) in which half of a player’s bet is returned to them if the ball ends up on zero.
The earliest known game of roulette was developed in the 18th century and is believed to have been influenced by the older games hoca and portique, with fanciful theories suggesting it was invented by 17th century French mathematician Blaise Pascal, by Chinese monks, or by the ancient Romans. By the late 1700s, the game had reached its present form and was widely popular in casinos and gambling dens throughout Europe.