Backgammon
Backgammon is a classic two-player game of luck and strategy. The goal is to
move all fifteen of your checkers into your home board and then bear them
off (remove them from the board). The first player to bear off all fifteen
checkers wins.
The Board
The board has 24 narrow triangles called points. Each player moves their
checkers around the board in opposite directions:
•
White (Player 1) moves from point 1 toward point 24. White's home board is
points 19–24.
•
Black (Player 2) moves from point 24 toward point 1. Black's home board is
points 1–6.
A bar in the middle holds checkers that have been hit.
Starting Position
Each player starts with fifteen checkers arranged in the standard position (from
each player's own perspective): two on the 24-point, five on the 13-point, three
on the 8-point, and five on the 6-point.
Taking a Turn
1.
Roll the dice. On your turn, roll the two dice.
2.
Move checkers. The two numbers tell you how far you may move. You can move
one checker by each die, or one checker by the sum of both dice (moving it one
die at a time, landing on an open point in between).
3.
Doubles. If both dice show the same number, you play that number four
times, split across any of your checkers.
You must use as many dice as you legally can. If you have no legal move, your
turn is forfeited automatically.
Where You Can Land
A checker may land on an open point — one that is empty, holds your own
checkers, or holds exactly one opposing checker. A point holding two or
more opposing checkers is blocked.
Hitting and the Bar
A lone opposing checker on a point is a blot. When you land on a blot you
hit it: the checker is sent to the bar.
If you have any checkers on the bar you must bring them back into play before
making any other move. A checker re-enters on your opponent's home board on a
point matching one of your dice. If neither die gives you an open entry point,
your turn is forfeited.
Bearing Off
Once all fifteen of your checkers are in your home board you may begin bearing
off:
•
A die bears a checker off the point matching that number (counting from the
edge of your home board).
•
If you roll a number higher than your highest occupied point, you bear a
checker off that highest point.
If one of your checkers is hit while you are bearing off, it goes to the bar and
must travel all the way around and back into your home board before you can
resume bearing off.
Winning
The first player to bear off all fifteen checkers wins the game.
Simplifications
This implementation makes two small simplifications to the traditional rules:
•
The opening roll is not a single-die roll-off — White simply takes the first
turn and rolls both dice.
•
The "must play the larger die when only one can be used" preference is not
enforced; you are only required to keep playing while a legal move exists.