This is known as the cancellation system. Pick a series of numbers, say 1,2,3,4,5. Your first bet is the total of the two numbers on the end, or 6 units in this case. If you lose it, you cancel out the 1 and the 5, add the six to the end of the series and bet the 6 and the 2, for a total of eight units bet. Lose that one and you add the eight to the series, cancel the 2 and the six and bet a total of 11 (3+8) and so on. If you win, you proceed to the inside numbers until they are all cancelled out. Again, a loser, but an insidious one.

According to Richard Epstein, craps is descended from an earlier game known as Hazard, that dates to the Middle Ages. The formal rules for Hazard were established by Montmort early in the 1700s. The origin of the name craps is shrouded in doubt, but it may have come from the English crabs, or from the French Crapeaud (for toad)