# Backgammon

Backgammon

Game Rules

Backgammon is a game for two players, played on a board consisting of twenty-four triangles called points. The triangles are grouped into four quadrants of six triangles each. The quadrants are referred to as a player’s home board and outer board, and the opponent’s home board and outer board. The home and outer boards are separated from each other by a ridge called the bar.

Figure 1.  A board with the checkers in their initial position

Each player has fifteen checkers. The initial arrangement of checkers is: 2 on each player’s 24 point, 5 on each player’s 13 point, 3 on each player’s 8 point, and 5 on each player’s 6 point. Both players have their own pair of dice. A doubling cube, with the numerals 2, 4, 8, 16, 32, and 64 on its faces, is used to keep track of the current stake of the game.

Object of the Game

The object of the game is to move all your checkers in circle into your own home board and then bear them off. The first player to bear off all of his checkers wins the game.

Figure 2.  Direction of movement of White’s checkers. Opponent’s checkers move in the opposite direction.

`The movement of checkers`
```To start the game, each player throws a single dice. This determines both which player will start
first and the numbers to be played. If equal numbers come up, then both players roll the dice again until they roll different numbers.
The player throwing the higher number now moves his checkers according to the numbers showing on both dice.
After the first roll, the players throw two dice and alternate turns. The roll of the dice indicates how many points the player can move his checkers.
The following rules apply:```

1. A checker may be moved only to an open point, one that is not occupied by two or more opposing checkers.

2. The numbers on the two dice constitute separate moves. For example, if a player rolls 4 and 6, he may move one checker four spaces to an open point and another checker six spaces to an open point, or he may move the one checker a total of ten (4 + 6) spaces to an open point, but only if the intermediate point (either four or six spaces from the starting point) is also open.

Figure 3.  Two ways that White can play a roll of

3.  A player who rolls doubles plays the numbers shown on the dice twice. A roll of 6 and 6 means that the player has four sixes to use.

A player must use both numbers of a roll (or all four numbers of a double) possible if this is legally. When only one number can be played, the player must play that number. Or if either number can be played but not both, the player must play the larger one. When neither number can be used, the player loses his turn. In the case of doubles, when all four numbers cannot be played, the player must play as many

Hitting a checker

A point occupied by a single checker of either color is called a blot. If an opposing checker lands on a blot, the blot is hit and placed on the bar. Any time a player has one or more checkers on the bar, his first obligation is to enter those checkers into the opposing home board. A checker is entered by moving it to an open point corresponding to one of the numbers on the rolled dice if the prospective point is not occupied by two or more of the opponent’s checkers.

Figure 4.  If the player rolls with a checker on the bar, he must enter the checker onto opponent’s 4 point since the opponent’s 6 point is not open.

If neither of the points is open, the player loses his turn. If a player is able to enter some but not all of his checkers, he must enter as many as he can and then forfeit the remainder of his turn. After the last of a player’s checkers has been entered, one can move any checker.

Bearing off

Once a player has moved all of his fifteen checkers into his home board, he may commence bearing off. It is done this way: a player bears off a checker by rolling a number that corresponds to the point on which the checker resides, and then removing that checker from the board. Thus, rolling 6 allows the player to remove a checker from the point 6.

If there is no checker on the point indicated by the roll, the player must make a legal move using a checker on a higher-numbered point. A player is under no obligation to bear off if he can make other moves.

Figure 5. The player rolls  and bears off two checkers.

A player must have all of his active checkers in his home board in order to bear off. If a checker is hit during the bearing-off process, the player must bring that checker back to his home board before continuing to bear off. The first player to bear off all fifteen checkers wins the game.

Doubling - Cube

Each Backgammon game starts at one point. During the course of the game, a player who feels he has a sufficient advantage may propose doubling the score. He may do this only at the start of his own turn and before he has rolled the dice. In case the player who is offered a double refuses, he concedes the game and loses one point. Accepting the double, the game continues with a doubled score. 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 loses 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 score. There is no limit to the number of redoubles.

Gammons and Backgammons

At the end of the game, if the losing player has borne off at least one checker, he loses only the value showing on the cube (one point, if there has been no doubling). However, if the loser has not borne off any of his checkers, he loses by Mars twice the value of the doubling cube. Or, worse, if the loser has not borne off any of his checkers and still has a checker on the bar or in the winner’s home board, he loses by Koks three times the value of the doubling cube.

• Beaver. 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.

• Jacoby rule. Mars and Koks count only as a single game if neither player has offered a double during the course of the game. This rule speeds up play by eliminating situations where a player avoids doubling so he can play on for a Mars.

Long backgammon

The rules of the game

The starting position in Long backgammon

There are two players in the game. In the game is used a special board divided into two halves. (left and right).

Each player has 15 checkers which are placed along right side of their boards’ half. The players’ checker sets have different colours, commonly they are white and black. The players use 2 dices (zars). During the game players throw dices by turn.

Each player can move only his own checkers.

Pic.1 Initial of checkers position

The checkers initial position on the board (position 1 and 13) is called “head”, and the move from that position is called “head move” (“take from the head”). During one head move the player can take only one checker.

The right of the first move and the white checkers are played as follows: each player throws one dice.

The players are casting lots, the right of the first move and the white checkers receives the one who throws out a higher score.  If the score is similar, the players have to repeat their throws.

The players move is a throw of the dices and the move of the checkers after the throw.

The move is done when the player after it gives the dices to his opponent.

The sense of the game

The player needs to pass with all his checkers  a fool circle (counter clockwise) and enter with them  into “home” and then “throw out” them before the same does his opponent. The “home” for each player is the last quarter of the playing field, which comes after 18 squares from the “head”.

The term “throw out” means to do such a move with a checker that can appear beyond the board limits. The player can “throw out” the checkers only after all of them “came home”. Therefore, the whites move from position 13 – 18 to position 7 – 12, the blacks from location 1 – 6  to 19 – 24  (Pic. 2).

(Pic. 2)

Playing the  game

The player throws two dices at the same time. After the throw player moves any of his checkers on the number of squares equal to the number of scores on dices.If on one of the dices was thrown out three, and on another one five, the player can move one of the checkers on three squares, and another on five. He also can move one checker on eight squares. It doesn’t matter which move to do first with high score or with the lower one.

(Pic.3)

The first throw of the match is an exception of the rules above.
If the first checker you can take from the head can’t do the fool move, it’s possible to take the second one.
There are only three throws that can bring to such situation:

Six – six (6**6)

Four – four (4**4)

Three – three (3**3)

It’s impossible to play the fool move by one checker in such situation, because the opponent’s checkers on the head hinder. If it drops out one of those combinations, the player can take two checkers from the head.

Note: If blacks threw out 4 – 4 after the whites had thrown out 5 – 5, they need to make only one move for four squares, because of the created hindrance.

It’s impossible to move two checkers on the number of squares shown by one dice, and then on a number of squares shown by another one. Other words, if there were thrown out five and four scores; player has no opportunity to move one checker on two squares, and the other one on three (to play five scores with two checkers) and then play the same way for the four.

If on the both dices the player has the same score (double, gosh, jackpot) the score doubles, it means that he can play as if he had thrown out four dices, he can move four times on the number of squares, that were thrown out on one dice.

It’s forbidden to put a block (obstacle, bridge) from six checkers, if there is no opponent’s checker in front of the obstacle you made. ( Pic. 4)

(Pic. 4)

It’s not forbidden to build a six-checker obstacle but you can’t lock all fifteen checkers of your opponent. You can build six-checker obstacle only if there is at least one opponent’s checker in front of it.

If the opponent’s checkers occupy six squares in front of any of your checker it appears to be locked.

If the checkers are locked in such way that the player can’t make any move according to the score he has thrown out on the dices (the checkers “doesn’t move”) the score vanishes, and the checkers don’t move at all.

You can put any amount of checkers on one square.You can’t put a checker on a square occupied by your opponent’s checker.

If the checker gets on an occupied square, it means it “doesn’t move”.

If the player has an opportunity to make the move shown by one of the dices, and has no chance to make the move shown by another one, he makes only one move. The score of the second move vanishes as the checker doesn’t move.

If the player has an opportunity to make the full move, he can’t reduce it, even if it’s in his interests. It means , if “ three” is favorable  for the player but he got “six” and he has an opportunity to move “six”, he has to move six.

If it was thrown out such a stone that the player can make only one move, any of two possible ones, he has to choose the higher one. The lower score will vanish.

Note:  the term “stone” in backgammon can mean the dice and the combination of scores thrown out on the dices.For example, the combination “four – three” is a stone.

To throw out checkers means to make such moves after which the checker will appear beyond the board limits. The player can begin throwing out the checkers only after all of his checkers came home.

In the process of withdrawing the checkers from the home player has a right to use the scores, thrown out on the dices the way he wants: he can play the checker in the home or throw it out.

You can throw out only the checker which is on the square relevant to the score thrown out on dices.

For example, if the player throws out 6 – 3, he can remove one checker from the sixth square and one from the third (three can be played from 6, 5 and 4 squares).

In the process of withdrawing the checkers from your field it’s possible to withdraw the checkers from the law grade squares, if there are no checkers on the higher ones.

For example, if it was thrown out 6 – 5 and the player has no checkers on that squares, he can withdraw checkers from the square next in turn, the fourth, if he has no checkers on that square too,  the third, if there is nothing there too, the second and etc.

Scoring in the game

The position, when the loser managed to throw out at least one checker, is called the “oin” (match, set) is lost (0 – 1).

The position, when one of the players has thrown out all his checkers, and the opponent  hasn’t managed to throw out any of his, is called to put a “mars” (win a game, to put a checkmate) ( 2 – 0).

Hyper-Backgammon

Game Rules

The starting position in Hyper-Backgammon

Hyper-Backgammon is a game for two players, played on a board consisting of twenty-four triangles called points. The triangles are grouped into four quadrants of six triangles each. The quadrants are referred to as a player’s home board and outer board, and the opponent’s home board and outer board. The home and outer boards are separated from each other by a ridge called the bar.

Each player has 3 checkers. The initial arrangement of checkers is: each player has a checker in the 24th, 23rd and 22nd (the 1st, 2nd and 3rd) points.

Figure 6.  The initial arrangement of checkers on the board in Hyper-Backgammon.

Nackgammon

Game Rules

This game is similar to Backgammon, but differs in the initial arrangement of checkers: in each row where 5 checkers were placed, one checker is off and a row of two checkers is added on the second line.

```Figure 7.  The initial arrangement of checkers on the board in Hyper-Nackgammon.
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