The earliest copy of the rules of backgammon are found in an epigram of Byzantine Emperor Zeno, who lived between 425 and 491 AD. With an age and pedigree of that magnitude, it's somewhat surprising that backgammon doesn't enjoy the elevated status of chess. Still, it remains a fun game that combines luck, skill and strategy to achieve success.
Backgammon involves two players facing off on either side of a board. Unlike chess or draughts, a backgammon board has no squares. Instead, there are 24 narrow triangles called points, 12 on each side, which alternate in colour. The points are divided into four quadrants, corresponding to the "home board" and "outer board" of each of the two players, and a bar divides the board down the middle, between the home/outer quadrants.
In these areas, each player arranges their 15 draught-like pieces according to a pre-determined layout, and attempts to advance toward their home board, from where they can remove all their pieces from the board. The winner is the first to clear their pieces.
The board is laid out with the centre bar running from one player to the other (joining, not dividing them). The home quadrants and outer quadrant are assigned to be directly opposite each other, not diagonally opposite. So if the white player's home board is on his/her right, the black player's home board will be on his/her left
Each player's points are numbered 1-24, starting at the first point of their home board and ending at the final point in the opponent's home board. Pieces are arranged as follows: two pieces on point 24, five on point 13, three on point eight and five on point six.
Players roll one dice each, and the highest number starts – if the numbers are the same, repeat until they differ. The player with the higher number plays his/her first move using the current roll. Subsequent movement is dictated by repeatedly rolling the dice
The objective of the game is to move all of the pieces into the home board, and then to bear them off. The winner is the first player to remove all of his/her pieces from the board.
Dice must be rolled together, onto the flat surface of the right hand section of the board; if this rule is broken, or one/both of the die don't lie flat, the player must re-roll. A turn is considered complete only once the person in play picks up his/her dice.
A turn is accepted (as legal) when the next player rolls the dice for their turn. If a player rolls the dice before their opponent has finished their turn, they forfeit their roll.
Once the game has started, players progress in a U-shape towards their home board, and their opponent moves in the exact opposite direction.
Each dice represents one move, so if a five and a three are rolled, the player must move one piece five spaces toward their home board and then another three. The same piece may be moved twice, amounting to a move of eight. If a double is rolled, each dice represents two moves: ie double six would mean four moves of six spaces. A piece can only move onto a point that is not already occupied by two or more opponent pieces (an "open point"). Players may not move pieces backwards, away from the home board. If a player can move a piece, s/he must do so.
A point occupied by just one piece is called a "blot", and it's open to a strategic attack called a "hit". When a player can move a piece onto a blot, it hits the opponent's piece, which must be removed from the board and placed on the centre bar. Any player with a piece on the centre bar must move this back into the game via their opponent's home board before moving any other pieces. If there aren't available points free to reintroduce the piece, the player forfeits their turn.
Once all 15 pieces are in a player's home board s/he may begin "bearing off" (removing the pieces). Players must bear off pieces according to the numbers rolled on their turn. For example, rolling a six and a four would mean pieces on points six and four can bear off. Alternatively, one piece from point six can be moved to point two and another can bear off. If a six is rolled and there are no pieces on point six, the player must bear off a piece from the next highest point. The first player to bear off all 15 pieces wins.
Scoring is usually done with a doubling cube. At the start of a game it sits on one, and when a player has an advantage s/he may propose a double. If the other player refuses, s/he concedes the game and a single point, if s/he accepts, the stakes are doubled. No player may propose a double twice in a row: ie once a double has been agreed, control of the doubling cube passes to the player who accepted the double.
If the losing player has not borne off any pieces, s/he is "gammoned", and the winner is awarded double points. If the loser has any pieces left on the bar, or on the winner's home board, s/he is "backgammoned" and the winner earns triple points.
According to the US Backgammon Federation, there are three commonly used optional rules, which are:
As explained, these rules are simply optional and are not required for an official game of backgammon but can certainly add a little excitement to this timeless game.