Despite its complicated rules, hazard was so popular in the 17th and 18th centuries that it was often played for money; games of chance were thus called "hazard games." At Crockford's Club in London, hazard was especially popular. In the 19th century, the game craps developed from hazard through a simplification of the rules.
In each round, the caster specifies a number between 5 and 9 inclusive: this is the main. He then throws two dice.
This is simpler to follow in a table:
|5||5||2, 3, 11, 12||Anything else|
|6||6, 12||2, 3, 11|
|7||7, 11||2, 3, 12|
|8||8, 12||2, 3, 11|
|9||9||2, 3, 11, 12|
As long as he keeps winning, the caster may keep playing: but if he loses three times in succession, he must pass the dice to the player to his left, who becomes the new caster.
Bets are between the caster and the bank (the setter), which may be the remaining players acting as a group.
If the caster nicks on the first throw, he wins an amount equal to his stake. After the first throw, the caster wins his stake if he gets his chance before his main.
After the first throw, the caster (and others, in side bets) may wager an additional sum that the chance will come before the main. These bets are made at odds determined by the relative proportions of the main and the chance:
For example, with an odds stake of £10, a main of 7 and a chance of 5, a castor stands to win £15 (3/2 × £10); with the same stake, a main of 5 and a chance of 6, he could win £8 (4/5 × £10).
For each main the probability of winning can be calculated:
|Main||Probability of Winning||Disadvantage to Caster|
In some reports on the rules of the game, the main is determined randomly by tossing the dice until a valid main appears. In this case the overall player disadvantage is 1.84%. If the caster can choose a main, he should always choose 7. This may be how craps evolved, since if you always choose 7 the game is basically just craps.
At its heart, craps is a version of Hazard where the main is always 7:
However, betting in craps is significantly more complicated.