In Craps, winning or losing depends on a variety of different possible outcomes on any roll of the two dice. The two dice can produce many different number combinations; some can be made several ways, others only one way. For example, two dice can roll the number 6 as follows: 5/1, 4/2, 3/3, 2/4 and 1/5. But the number 2 can only be rolled one way: 1/1.

On the "Come Out" roll, the "Pass Line" bet wins if the shooter rolls a 7 or an 11. The bet loses automatically if the shooter rolls 2, 3 or 12. This is known as "rolling craps". If the shooter rolls 4, 5, 6, 8, 9 or 10 the shooter must roll this same number again (to win) before rolling the number 7. Rolling any of these numbers on the "Come Out" roll is called "establishing the "Point". Any number so rolled is thereafter referred to as the "Point".

The shooter, or anyone wishing to bet that the shooter will win, places his bet "on the line" (in the area marked "Does Pass," "Line," or "Win" on various layouts) Anyone betting against the shooter places his bet in the area marked "Don't Pass." Anyone wishing to bet on a special contingency, such as that craps (2, 3, or 12) will or will not be thrown on the next roll, places his bet in the appropriate space on the layout; such bets are called proposition bets. The house maintains a mathematical advantage on all bets of about 1.4 percent, higher on certain layouts and special bets.

The inside walls of the table are covered with a serrated egg-carton like foam, designed to make the dice bounce around to assure randomness. Each throw of the dice is called a "roll". Players take turn rolling the dice, clockwise around the table, and the player rolling at any given time is called the "shooter". When a new shooter is given the dice, his or her first roll is called the ""Come Out"" roll. This begins a new series of rolls by that shooter and lasts for as long as that shooter continues to make winning rolls.