Roullete is a casino game with many different bets that can be made. A player can bet on a single number, various groupings of numbers (red or black), whether the number is odd or even, and if the bet is high (19-36) or low (1-18). Other bets are on red or black, or if the number is in one of the three arcs around the wheel.
The game was developed in France at the end of the 17th century, and Blaise Pascal is credited with being its creator. It was based on older games such as hoca and portique. It achieved its present layout and wheel structure about 1790.
A roulette wheel consists of a solid, slightly convex wooden disk with a rim holding 37 compartments or pockets painted alternately red and black. There is also a green pocket which carries the sign of 0, and on American-style wheels there are two more green pockets on opposite sides of the wheel. The wheel is balanced by a spindle and rotates in an almost frictionless manner.
A ball is rolled into the wheel, and winning bets are paid out according to their odds. Each bet has a different payout depending on its type. Outside bets are the easiest to understand since they cover multiple numbers and pay a lower amount. Other bets like the Dozens and Columns have specific areas where they can be placed on the table, and are more complex to determine the payout. A good rule of thumb is to always know the expected return for each bet before you place it on the table. This way you will know when to walk away.