The roulette wheel has pockets numbered from 1 to 36. The pockets with numerals ranging from 1 to 10 and 19 to 28 have odd numbers colored in red and the even ones in black, while the pockets with numbers ranging from 11 to 18 and 29 to 36 have odd numbers colored in black and the even in red. The French roulette displays a green pocket containing the number 0 (zero); the American version has a second green pocket marked with 00. The roulette wheels have this number placement sequence:

French single zero roulette wheel 0-32-15-19-4-21-2-25-17-34-6-27-13-36-11-30-8-23-10-5-24-16-33-1-20-14-31-9-22-18-29-7-28-12-35-3-26

American double zero roulette wheel 0-28-9-26-30-11-7-20-32-17-5-22-34-15-3-24-36-13-1-00-27-10-25-29-12-8-19-31-18-6-21-33-16-4-23-35-14-2

The betting area on a roulette table is called the layout. The  French layout has a single zero and the American one exhibits both a single and a double zero. The French style layout, with the wheel in the center of the roulette table, can still be found in the Monte Carlo casino. The American style layout, which places the wheel on one of the table sides, can be encountered in almost all the casinos in the world.

Straight (or Single) You wager on a single number, by positioning the chip in the center of a numeral square on the roulette table.

Split Split is a bet on the line that separates two numerical squares on the roulette table, placed either on the vertical line or the horizontal one (as in 14-17 or 8-9).

Street Street is a bet on a single horizontal line comprising three numbers: the chip has to be situated on the edge at the line’s end.

Corner (or Square) Corner is a bet placed on four numbers that are in a square layout (as in 11-12-14-15). The chips/chip are/is placed at the intersection of the vertical and horizontal lines that run through the four square numbers.

Six line (or Double Street) Six line is a bet on two neighboring streets – the chip will be placed at the corresponding intersection.

Trio Trio is a bet placed at the intersection between 0, 1 and 2, or 0, 2 and 3 (this applies only to the single-zero layout).

Basket (or the first four) Basket is a non-square corner bet on 0, 1, 2, and 3 (this also applies only to the single-zero layout).

Top line Top line is a bet on the numbers 0, 00, 1, 2, and 3 (this is valid for the double-zero layout only). The chip can be placed either on the corner of 0 and 1 or that of 00 and 3.

Outside bets have better odds at winning but offer smaller payouts.

Bet on 1 to 18 (Manque in French)

This is a bet placed on one of the first, low eighteen numbers.

Bet on 19 to 36 (Passein in French)

This is a bet placed on one of the latter, high eighteen numbers.

Red or black (Rouge ou Noir in French)

This is a bet on which color the roulette wheel will display.

Even or odd (Pair ou Impair in French)

This is a bet placed on even or odd  numbers and does not include 0.

Dozen bets

For these you have three choices: P12(premier douzaine in French) or the first dozen(1-12), M12 (Mayenne douzaine in French), a.k.a. the second dozen(13-24) and D12 (Derniere douzaine in French), which is the third dozen (25-36).

Column bets

They are wagers placed on all twelve numbers on any of the 3 vertical lines of the roulette table layout, with the chip positioned in the space below the final number in this column.

The house edge or house advantage is the amount of money that a player loses on average for any bet he makes. For example, in the American format there is a probability of 1:38 that a player will win a bet on a single number and also there is the possibility of 37:38 that the player will lose when he makes the same bet. For American Roulette, you can calculate the house edge using this equation:

−1×37⁄38 + 35×1⁄38 = −0.0526 (5.26% house edge)

In the case of European roulette, a single number bet sets the probability to win at 1 in 37 and to lose at 36 in 37, here you can calculate the house edge this way:

−1×36⁄37 + 35×1/37 = −0.0270 (2.70% house edge)

Technically, the 0 and 00 pockets on the roulette wheel constitute the only advantage of the house. This is because when you make an outside bet, you will always lose if the ball lands in one of the 0 and 00 pockets, but in fact this is not the only house edge because they only pay 35 to 1 for a winning single bet, even if mathematically there is the probability of 1 out of 37 (1 out of 38 for American Roulette) to win a bet on a single number. For example, if you place a one-dollar bet on all inside numbers and also 0 and 00, you will certainly win, but only $35 when your original bet cost you $38.

In the early ages of gambling, the house could set the odds at 27 to 1: this meant that upon betting $1 you would win $27 and the house kept your dollar. Nowadays, the casino odds are set by law and they must be either 35 to 1 or 34 to 1.