The game of Roulette centers around a wheel with thirty-eight numbered bins. The numbers include 0, 00 (double zero), 1 through 36. The table has a surface marked with spaces on which players can place bets. The spaces include the 38 numbers, plus a variety of additional bets, which will be detailed below. After the bets are placed by the players, the wheel is spun by the house, a small ball is dropped into the spinning wheel; when the wheel stops spinning, the ball will come to rest in one of the thirty-eight numbered bins, defining the winning number. The winning number and all of the related winning bets are paid off; the losing bets are collected. Roulette bets are all paid off using odds, which will be detailed with each of the bets, below.

The numbers from 1 to 36 are colored red and black in an arbitrary pattern. They fit into various ranges, as well as being even or odd, which defines many of the winning bets related to a given number. The numbers 0 and 00 are colored green, they fit into none of the ranges, and are considered to be neither even nor odd. There are relatively few bets related to the zeroes. The geometry of the betting locations on the table defines the relationships between number bets.