The easiest explanation of CRAPS available!

Craps is a large table game played by several players at once, with one of the players, who rolls the dice called the shooter.  Players take turns being shooters.

Before a shooter rolls the dice players place their bets.  The shooter's first roll of the dice is called the "come out roll.” in which in which two dice must be thrown in such a way that they hit the opposite wall of the game table.  Shooters pass their turn to the next person when they loose.

If a 7 or 11 come up, the shooter wins, and if 2, 3, or 12 come out– he loses.   The remaining numbers 4, 5, 6, 8, 9 and 10 are called the "point" if they come up. When a shooter rolls the point, he or she must continue rolling the dice until the same “point” number OR a 7 comes up. If the point comes up first, he wins. If a 7 or 11 come up first, he loses.

Everyone else: can make these bets:

1 Pass Line: Wins and loses on the same outcomes as the shooter. So you also win if 7 or 11 appear on come our roll, but lose if a 7 appears after the game goes into “points”. 

2 Don't Pass Line – Opposite of a Pass the Line bet. Don't Pass Line bets win if the come out roll is 2 or 3, and lose if it is 7 or 11. If a come out roll is 12, the bet becomes a "push" and the player gets his money back. If a number other than 2, 3, 7, 11, or 12 appears, it becomes a point, and this bet wins the same way as the shooter’s bet, waiting for the right point. 

Come Bets – Similar to pass the line bet, but made after come out roll has already established a point number. This bet is made on the next shooter’s roll as if you were making a pass line bet on a first, come out roll.

Don't Come Bets - Similar to Don't Pass Line bets, but made after come out roll has already established a point number. Don't Come Bets win if the shooter's next roll is 2 or 3, but lose if the roll is 7 or 11, and push if the roll produces 12. Don't Come Bets win if the shooter's next roll produces a 7 before the come point.

Place Bets - This bet works only after the point has been determined. You can bet on a dice roll of 4, 5, 6, 8, 9 and 10. You win if the number you placed your bet on is rolled before a 7. Otherwise you lose. The Place Bets payoffs are different depending on the number you bet on. 4 or 10 will pay 9:5; 5 or 9 pays 7:5, and 6 or 8 pays 7:6. You can cancel this bet anytime you want to. 

Field Bets - These bets are for one dice roll only. If a 2, 3, 4, 9, 10, 11, 12 is rolled you win. A 5, 6, 7 and 8 make you lose. Field bets have the following different payoffs: 2 pays double (2:1) while a 12 pays 3:1. Other winning dice rolls pays even (1:1).

Big Six, Big Eight Bets - Placed at any roll of dice these bets win if a 6 or 8 come out before a 7 is rolled. Big Six and Big Eight are even bets and are paid at 1:1.

Any Craps: Wins if a 2, 3 or 12 are thrown. Payoff 8:1

Any Seven: Wins if a 7 is rolled. Payoff 5:1

Eleven: Wins if an 11 is thrown. Payoff 16:1

Ace Deuce: Wins if a 3 is rolled. Payoff 16:1

Aces or Boxcars: Wins if a 2 or 12 are thrown. Payoff 30:1

Horn Bet: it acts as the bets on 2, 3, 11 and 12 all at once. Payoff is determined according to the number rolled. The other three bets are lost.