In Craps, the Marker Puck is placed on the table by the dealer to show the status of the game. If the puck is white and placed on a specific number, it indicates that a point has been established, and the shooter must roll that number again before rolling a 7 to win. If the puck is black and placed off to the side, it means no point is currently active.
Marker Puck Example
For example, when the shooter rolls a 4, the dealer places the white Marker Puck on the 4. The shooter now needs to roll a 4 again before rolling a 7 to win.