Backgammon is a game, which uses checkers, dice and dice cup along with a doubling cube on a board of 24 triangles (points) as instruments in a small battle on the playing field.
Each player has fifteen checkers, which he sets up in the following fashion (insert starting position [position one] here) as his opponent sets up his checkers of a different color in a mirror position.
The objective of the game is to move all of your fifteen pieces into your home quadrant of six points and then take them all off the board before your opponent achieves that same goal.
The movement of the pieces is dictated by the number of spots on each of the two dice rolled. As in chess or checkers only one player can move his pieces at a time and to determine who moves first each player takes one die and rolls it onto the right side of his board on the playing surface.
The player with the higher number plays both numbers and moves either one checker or two separate checkers the corresponding number of spaces equivalent to the spots on each die. In case of a tie, each player rolls one die again until there are different numbers for each player.
The movement is as follows. You can only move your pieces forward in a horseshoe fashion. If your home board is on the right side of your board you move from right to left on the top side of the board and left to right on the bottom side. Your opponent moves in the opposite direction of you and there is a battle that takes place, as each side's goal is to get all of their checkers into their home section of six points.
After the first move is completed, the player with the larger number on his die picks up his die and puts it back into his cup with the other die. The player who hasn't moved yet then picks up his die and puts it into his cup with his other die and then shakes both dice in the cup and rolls them onto the right side of his board.
He then must move either one checker the same number of spaces on the board that corresponds to the number of spots on both dice or two separate checkers corresponding to each individual die. For example, if you roll a three on one die and an one on the other die you may move a single checker from the eight point to the four point (enter pos 2a here) by either moving three spaces and then one space or by moving one space and then three. As an additional note, when moving over the bar (the raised surface dividing the two halves of the board) you don't count landing on the bar as movement of a space. You count crossing the bar from one side of the board to the other side of the board as movement of one space
A more insightful player or one who has experience with the game would see that you could move one checker three spaces from the eight point to the five point and another checker one space from the six point to the five point.(enter pos 2b here)
There is an advantage in moving two separate checkers to the same triangle (point) in that you then have defensive control over that point. The reason is that anytime you have two or more checkers on a single point your opponent may not land on that point. He may leap over that point using a larger number but he may not land on that point.
If a player on his second roll or subsequent rolls, rolls the same number on both dice that is referred to as a "double" and he then must move whatever that number was four times. For example if he rolls a double three, he may move one checker three spaces, four different times or four separate checkers three spaces each. He also may move any other combination of three spaces moved four times (two checkers moved three spaces twice, one checker moved three spaces and a separate checker moved three spaces three times or two separate checkers moved three spaces once and a third checker moved three spaces twice).
As long as a total of 12 spaces are moved (four movements of three spaces) for the given example of "double threes". Obviously if the double were different, for example double sixes, then you must move six spaces four separate times to fulfill your obligations for that move.
On your move you may land on any empty point or point in which you have any number of your own checkers, but not on a space where your opponent has two or more checkers since he would have control of that space by virtue of having that "point". You could also land on a space in which your opponent had exactly one checker.
One checker, which is also referred to as a blot, is vulnerable to being displaced by his opponent when a number is rolled that allows movement to exactly that space on the board.
Since by the rules of backgammon checkers of two different colors may not occupy the same space at the same time the checker, which newly arrives at that space now displaces the opponent's checker and puts it on the bar.
The bar as I mentioned before is the raised dividing line between the two halves of the backgammon board is the place where you send checkers that have been displaced (hit).
In games like parchesi, sorry, or trouble you send opponents back to starting points and that is what the bar is in backgammon.
After your opponent has finished his move and picked up his dice it is then your turn again. After you roll your dice you must then attempt to enter any checkers that are on the bar.
To do this you may place any checkers on the bar on your opponent's home board is the number of the die corresponds with any non occupied point by your opponent.
You may land on any empty space. You may land on any space in which you have a single checker (blot) or multiple checkers (point). You may land on any space in which your opponent has a blot (hitting your opponent) but you may not land on any space in which your opponent has two or more checkers (opponent's defensive point).
The number of the point in your opponent's home board is from six to one beginning at the point next to his bar and moving towards the bear off tray. The point next to the bear off tray is the one point. (enter pos 3 here)
The bear off tray, which can be different on different types of backgammon sets, is a place to put all your checkers, which you have successfully borne off. You are not required to put your checkers in the bear off tray but you are required to keep them off the playing surface, which includes any point, the bar, or other spot in the playing field.
To continue play when you have pieces on the bar you must enter all checkers on the bar before making any other moves. For example, if you can not enter at all because the number you rolled is the same as the numbered points in your opponent's home board your play is over. That is referred to as "dancing", "fanning", or "bouncing". (enter pos 4a here)
If you can only enter a portion of the number of checkers on the bar you must enter those checkers and your play is over. (enter pos 4b here) You may not use the number rolled for any other purpose until you enter all of your pieces on the bar.
Once you have entered all your checkers from the bar you may continue to move pieces in that oval horseshoe fashion towards your home quadrant of six spaces.
In the process of moving your pieces you will encounter some resistance. This may come in the fashion of a blockade. This is also referred to as a prime. Since making points is generally an asset for you then making consecutive points is usually more of an asset.
Your opponent may not land on any of your points but he may leap over those points if he rolls a number greater than the length of that prime. If you have four consecutive points he must roll a five or a six to jump over that prime.
If he rolls a three and two he may not add those numbers together to jump five spaces as he is required to move the corresponding spaces designated by each die separately. (enter pos 5a here). If he however rolls a five on a single die then he may jump over that prime. (enter pos 5b here and 5b1)
If you can make a prime of six points in a row your opponent may not jump over that prime at all since the highest number on a single die is six he can not move seven spaces.
Making a prime is not a foolproof way to win the game as your opponent will likely be trying to assemble a prime of his own to block you in. Battles such as these are referred to as "prime versus prime" battles.
This is more of an advanced topic, which you can get into as you begin to study the game. Since this article is a basic primer into understanding the game, you may be interested where you can get more information on how to improve your backgammon game.
"Backgammon" by Paul Magriel is considered a classic beginner text and is highly advised reading for anyone who is interested in taking up the game. Books for more advanced players are written by such authors as Bill Robertie, Kit Woolsey, and Walter Trice.
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