Roulette is one of the most popular casino games. It is easy to learn and has many betting options. Players can bet on single numbers, various groups of numbers, the colors red or black, odd or even, high or low.

The game combines elements of several older casino games and was invented in France by 17th century mathematician Blaise Pascal. It spread to casinos and gambling dens around Europe, where it became a major pastime for elite gamblers.

A roulette wheel consists of a solid wooden disk, slightly convex in shape and with thirty-six compartments (called frets or canoes by croupiers) painted alternately red and black, and numbered nonconsecutively from 1 to 36. A 38th compartment, painted green on American wheels and a 0 on European wheels, carries the sign of zero.

Roulette began its life in the illegal gambling dens of Paris and gradually gained popularity in the US where a double-zero wheel was used. However, in 1843 the French brothers Louis and Francois Blanc introduced a single-zero pocket on the wheel and this significantly reduced the house edge to its current level. This is known as European Roulette and it is the version that most players prefer in physical and online casinos. This is because it magnifies the chances of winning by a factor of 2.7%. There are also two rules within the game; en prison and la partage that further reduce the house edge. The en prison rule literally means ‘in jail’ and it returns half of a player’s even chip bets when the ball stops on zero.