Rules
There are two different layouts for the roulette table, one with the roulette wheel positioned at one end of the board with the betting area taking up the rest, and the other with the wheel positioned in the middle of the table, and areas for betting located on both ends of the table. The center of the board has the main 36 spaces laid out in 3 columns with 12 numbers in each. In European roulette, there is an additional 0 spot, and in American roulette, there is both a 0 and a 00.
The roulette wheel itself therefore has a total of either 37 (European) or 38 (American) slots for the ball to fall into. The slots are a distribution of alternating odd and even numbers, and alternating black and red numbers. 0 and 00 are neither odd nor even and green. The ball is generally made out of plastic, metal, or ivory. Each player uses a different color of marker, or chip, to place his or her bets.
This article is aimed towards players of American roulette. The only real difference, though, is the addition of the 00 slot in the American game, which effectively increases the house advantage. Some online casinos, however, have been known to offer bonus chips for the American version that are not available in the European version, due to the odds difference.
Basic Flow of the Game
A round of the game proceeds in this fashion: bets are made by players who place their markers on the positions on the board. The croupier (also known as the dealer), puts the wheel into a counterclockwise spin, and then rolls the ball into the track around the outside of the roulette wheel so it spins in a clockwise direction. Bets are allowed to be placed by players even while the ball is in motion along the wheel, until the ball begins to slow and the dealer states "No more bets." and all bets become locked in.
Eventually the ball will come to a rest in one of the slots on the wheel, and the croupier will announce both the number and color of the slot. The 0 and 00 slot is green, and is not odd or even and therefore can only be won by being bet upon directly. The losing bets are collected by the house and the croupier hands out chips to the winning players.
Odds
The proportion of the win to the bet depends on the odds of the bet you've made, with generally riskier bets paying out more, except for the five number line bet, which has a disproportionately poor payout. The main outlier of this system and the cause of the house advantage are the 0 and 00 slots, which cannot be bet upon collectively like other slots but still pay out the same. If, for example, 0 was red and 00 was black, there would be no house advantage as there would be a 1:1 chance and a 1:1 payout for the red and black positions, however this is not the case.
The house advantage in European roulette is only 2.70%, whereas the house advantage in American roulette is 5.26%, unless a player makes the mistake of making a five number line bet, which has a house advantage of 7.89%.
