The commonest craps roll is a SEVEN, which is made up of two dice with five letters. Craps is a popular dice game that originated in the United States and is now played in casinos around the world. In the game, players make wagers on the outcome of the roll of two dice. The most common roll is a SEVEN, which is made up of two dice with five letters. This roll has the highest probability of occurring, making it the most common roll in craps.