Backgammon is played for an agreed stake (number of points) per match. Each game starts at one point. During the course of the game, a player who feels he has a sufficient advantage may propose doubling the stakes. He may do this only at the start of his own turn and before he has rolled the dice.

A player who is offered a double is allowed to refuse, in which case he concedes the current game within a match and loses the current number of points. Otherwise, he must accept the double and play on for the new higher stakes. A player who accepts a double becomes the owner of the cube and only he may make the next double.

Subsequent doubles in the same game are called redoubles. If a player refuses a redouble, he must pay the number of points that were at stake prior to the redouble. Otherwise, he becomes the new owner of the cube and the game continues at twice the previous stakes. There is no limit to the number of redoubles in a game.

How do points and cube relate to each other?
When cube is set to any value [other than initial 64], this value is only meant to multiply OTHER normal gained game points.

Without the cube, the game within the match can earn 1 point [normal], 2 points [win with gammon] and 3 points [win with backgammon]

If the cube is set to 2 in a game:
* normal [1 point] win in the game will be worth 2 points
* gammon win [normally 2 points] will be worth 4 points
* backgammon win [normally 3 points] will be worth 6 points

Beaver

An immediate redouble by a player who just accepted a double. A player who beavers turns the cube up one level and retains possession of the cube.

When a player is doubled, he may immediately redouble (beaver) while retaining possession of the cube. The original doubler has the option of accepting or refusing as with a normal double.

