You can bet on red or black, odd or even, and individual numbers between zero and 36. You can bet on "dozens", which refers to the first 12 numbers, covering 1-12, the second 12 numbers between 13-24 and the third set of 12 numbers, which covers 25-36. You can also place bets on columns, which refers to the three columns made up of 12 numbers which run horizontally along the length of the table.