BACKGAMMON

• Introduction
• Board Set-up
• Object of the Game
• Game Rules
• Hitting and Entering
• Bearing Off
• Doubling
• Gammon and Backgammon
• Optional Rules

Introduction

Backgammon is a game for two players only. It is played on a board consisting of twenty-four narrow triangles of alternating color called points, which are grouped into four quadrants of six triangles each. Each quadrant is known as a player's or its opponent's home board and outer board. A ridge down the centre of the board called the bar separates the home and outer boards from each other.

The ancient Egyptian game senet resembled backgammon with moves controlled by the roll of dice. The Royal Game of Ur, played in ancient Mesopotamia, is a more likely ancestor of modern day tables games. Excavations at the "Burnt City" in Iran have showed that a similar game existed there around 3000 BC.

The ancient Romans played a number of games remarkably similar to backgammon. Ludus duodecim scriptorum ("Game of twelve lines") used a board with three rows of 12 points each, and the checkers were moved across all three rows according to the roll of dice. Tabula, meaning "table" or "board", was a game mentioned in an epigram of Byzantine Emperor Zeno (AD 476–481). It was similar to modern backgammon in that the object of the game was to be the first to bear off all of one's checkers. Players threw three dice and moved their checkers in opposing directions on a board of 24 points.

In the 11th century Shahnameh, the Persian poet Ferdowsi credits Burzoe with the invention of the tables game Nard in the 6th century. He describes an encounter between Burzoe and a Raja visiting from India. The Raja introduces the game of chess, and Burzoe demonstrates nard, played with dice made from ivory and teak.

The jeux de tables, predecessors of modern backgammon, first appeared in France during the 11th century and became a favorite pastime of gamblers. In 1254, Louis IX issued a decree prohibiting his court officials and subjects from playing.

Tables games were played in Germany in the 12th century, and had reached Iceland by the 13th century. The Alfonso X manuscript Libro de los juegos, completed in 1283, describes rules for a number of dice and tables games. By the 17th century, tables games had spread to Sweden. A wooden board and checkers were recovered from the wreck of the Vasa among the belongings of the ship's officers.

In the 16th century, Elizabethan laws and church regulations prohibited playing tables, but by the 18th century backgammon was popular among the English clergy.

In English, the word "backgammon" is most likely derived from "back" and Middle English "gamen", meaning "game" or "play". The earliest use documented by the Oxford English Dictionary was in 1650.

It is known as ifranjiah in Arabic (meaning "Frankish"), and is referred to as takhte nard in Iran. In Israel and the Middle East as well, it is known as shesh besh (meaning "six and five").

The most recent major development in backgammon was the addition of the doubling cube. It was first introduced in 1926 or 1927 in New York City among members of gaming clubs in the Lower East Side. The cube required players not only to select the best move in a given position, but also to estimate the probability of winning from that position.

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Board Set-up

In the graphic below, checkers are placed on the board in starting position.

The points are numbered starting in each player's home board. The last point is the twenty-fourth point, which is also the opponent's point number one. There are fifteen black checkers and fifteen white checkers. The initial arrangement of checkers is: two on each player's twenty-fourth point, five on each player's thirteenth point, three on each player's eighth point, and five on each player's sixth point.
Each player has a pair of dice and a dice cup to roll them.

A doubling dice with numbers 2, 4, 8, 16, 32, and 64 on its faces is sometimes used to multiply the points to be obtained in a match by as many times as indicated by the numbers mentioned above.

Object of the Game

The object of the game is for either player to move all its checkers into its own home board and then bear them off. The first player who manages to bear off all its checkers wins the game.

Movement of the black checkers. White checkers move in opposite direction.

Game Rules

Each player will throw a dice in order to begin the game. The first player to play will be the one who gets the higher number. It will first move its checkers as many points as shown by the number of the dice rolled. Every new match will have to be started in this same way.
Once the round begins, the opponent throws both dice.
The dice indicate how many points or pips a player can move its checkers. The checkers are always moved to a lower-numbered point.

The following rules must be followed:

• A checker may only be moved to a point not occupied by two or more opposing checkers, that is, an open point. A checker may pass over occupied points to end its move on an empty space, a space occupied by a player.s own checkers, or a space taken by only one opposing checker, which will be then sent to the bar. A checker may not, however, end its move on a point occupied by two or more opponent's checkers.
• The number on one of the dice enables you to make a movement separate from the move pointed by the number on the other dice. For example, if a player rolls 5 and 3, it may move one checker five spaces to an open point and another checker three spaces to an open point, or it may move one checker a total of eight spaces to an open point, provided points number 5 or 3 in-between from the starting point are also open.

To move a checker, a player drags it to its destination. If a player rolls doubles (both dice show the same number), it plays the number shown by each dice twice. A roll of 6 and 6 means that the player may make four moves of six pips with any combination of checkers.
A player must move both numbers of a roll if this is possible (or all four numbers of a double) and may not play one dice in such a way as to make the other dice unplayable. If only one number can be played, the player must necessarily play that number. If neither number can be moved without blocking the other dice movement, a checker must be moved as many pips as shown by the higher dice.
When neither number can be used, the player loses its turn. In the case of doubles, whenever all four numbers cannot be played, the player will have to move as many pips as possible.

Hitting and Entering

A point occupied by a single checker is called a blot. If an opponent checker lands on a blot, the checker in it is hit and placed on the bar. It is possible for a player to hit two blots in a single turn (one with each dice number), or as many as four on a roll of doubles. If a player has one or more checkers on the bar, it will have to enter those checkers into the opposite home board before it can move any other checker. A checker is entered by moving it to an open point according to one of the numbers shown by the dice. For example, if a player rolls 4 and 6, it may enter a checker onto either the opponent's fourth point or sixth point, as long as those points are not occupied by two or more opposite checkers. It can also enter a blot and send the single checker to the bar.

If white checkers. player rolls a 6/4 and has checkers on the bar, it must enter a checker into its opponent.s fourth point since the sixth point is not open.
If neither point is open, the player loses its turn.
If a player can only enter some but not all of its checkers because dice numbers prevent it from doing so, it will have to enter one checker and will lose the possibility of playing the other number.
Once a player has entered its last checker, any unused number on the dice will have to be played by moving either the checker that has been entered or a different one.

Bearing Off

Once a player has successfully moved its fifteen checkers into its home board, it may start bearing them off by removing from the board a checker which is on the point indicated by the number of the dice rolled. Thus, rolling a 6 allows the player to remove a checker from the sixth point.
If there is no checker on the point indicated by the dice, the player will have to move a checker placed on a higher-numbered point. If there are still no checkers on higher-numbered points, the player will be required to remove a checker from the highest point on which it has checkers.

A player is under no obligation to bear off if he can make an otherwise permitted move. In the following picture white checkers' player rolls 6/4 and bears off two checkers.

If the roll were 6-1, the normal movement would be to bear off the checkers on the 6th and 1st points, but it would also be possible, in case there is a single checker on point number 6, to move the checker on the 6th point one pip, and then, bear it off from the 5th point by using the six on the other dice. This movement is allowed as you are using both dice numbers with two permitted actions and would be advisable in a situation where black checkers. player has a checker on the bar, as shown in the graphic below:

Here, if the player bears off two different checkers (one for each number on the dice), it gives black checkers. player an opportunity to hit the checker on player.s 1st point by throwing a 1 and entering the checker on the bar there. If player chooses instead to use the 1 first, and then the 6 with the same checker, it will keep the safe position on its 1st point, from which both checkers can be borne off next turn with any roll of the dice.

Doubling

Backgammon is played for points previously agreed to. Each game starts to be played at one point. During the course of the game, either player may propose doubling the points at stake. It may only do this at the beginning of its own turn and before it has rolled the dice.
A player who is offered a double may refuse to accept it, in which case it concedes the game and pays one point. On the other hand, if it accepts the double, it keeps playing on for points doubled. A player who accepts a double becomes the owner of the doubling dice, which means that only it may make the next double proposal.
Subsequent doubles proposed during the same game are called redoubles. If a player refuses a redouble, it will have to pay the number of points that were at stake prior to the redouble proposal. Otherwise, it will become the new owner of the doubling dice, points at stake will be redoubled and the game will continue. There is no limit on the number of redoubles that may be proposed during a game.
64 is the highest number on the doubling dice.

Gammon and Backgammon

If one player bears off all its checkers before the opponent bears off any of its, the game is known as a gammon. It counts as a double game so that the winner is considered to have won twice, or scored twice the value of the doubling dice, if it has been used. If, in addition to having borne off no checkers, the loser still has at least one checker in the winner's inner board or in the bar, the game is called a backgammon. A backgammon counts as a triple game.

Optional Rules

The optional rules below are usually followed:

The Jacoby Rule

Gammons and backgammons count as a single game only if neither player has offered a double during the course of the game. This rule helps speed up the game by eliminating situations where a player avoids doubling.

The Crawford Rule

A player will not be able to double points at a time during the game when its opponent needs only 1 point to win the game.

Beaver

Whenever your opponent offers you to double and you believe that you have great chances of winning the game, you may beaver (double). If you do, you will be accepting the double, but redoubling and retaining the doubling dice at the same time.

Automatic Double

If you choose this option, the game will be automatically doubled if you and your opponent roll the same number on a dice at the beginning of the game. The dice is retained by neither player, but left in the center of the board. This option can only take effect once per game.