This board plays the standard rules of a single game: both dice must be used when they can be, a lone checker can be hit and sent to the bar, bearing off waits until every checker is home, and a gammon or backgammon is named when the loser has borne nothing off. You play White, moving anticlockwise into the home board at the bottom right. The computer weighs the race, the points each side holds and every blot's chance of being hit, and on Hard it rolls all of your replies before it commits. The dice decide a lot in one game; over many, the better plan wins.
The opening rolls
Your first move sets the shape of the game. The standard plays are worth learning by heart, because the computer knows them too.
- Make a point when you can. 3-1 makes your 5-point (8/5 6/5), 4-2 makes the 4-point (8/4 6/4) and 6-1 makes the bar point, your 7-point (13/7 8/7). A point held by two checkers can't be hit and blocks the computer's back checkers.
- Split and build with the rest. With 6-5, run a back checker to safety (24/13). With small rolls, bring a builder down from the 13-point and step a back checker up to the 21- or 20-point, where it can make an advanced anchor later.
- The 5-point is the one that matters. It's the strongest point in your home board: it blocks the sixes and fives your opponent needs to escape and gives your own hit checkers a safe landing place.
Points, primes and blots
Backgammon is a race, but the contact comes first. While the two sides still have to pass each other, structure beats speed.
- Hold points in a row. Three or four points next to each other are a prime, and a checker stuck behind one has to roll exactly past it. Six in a row is a full prime, which nothing gets past until you break it.
- Count the shots before you leave a blot. A single checker six or fewer pips in front of an enemy checker is a direct shot, hit by eleven to seventeen rolls out of thirty-six. Seven or more pips away it takes a combination, three to six rolls. Leave blots where the shot count is low, and never inside your own home board when the computer has a checker on the bar.
- Hit when it costs you nothing. Sending a checker to the bar costs its owner all the pips it had travelled, and it then has to enter against your home board. Hitting a blot in your outfield with a checker that lands safely is almost always right. Hitting loose in your own board is a gamble: you may be hit back from the bar.
- Keep an anchor until it's safe to run. Two checkers on the computer's 5- or 4-point (your 20- or 21-point) can't be attacked and give you something to land on when you are hit. Don't give it up until your back checkers can get past the computer's points.
When the contact ends
Once every checker has passed the other side's, there is nothing left to hit and the game is a pure race. Compare pip counts, shown under the board: the side with fewer pips to go is ahead, and the side on roll gains about eight pips of value.
Race efficiently. Bring checkers into your home board onto the 6-, 5- and 4-points rather than deep on the 1- and 2-points, where the extra pips are wasted. When bearing off, take a checker off whenever a die lets you; moving inside the board instead only costs you a roll. Try to leave an even number of checkers spread over the high points, so that doubles and big rolls all find something to take off.
Bearing off under fire
If the computer still holds a point in your home board while you bear off, every blot you leave can be hit, and a checker hit at that stage has to travel the whole board again. Clear your points from the back, the 6-point first, and keep the checkers you move in pairs. A die that can't be played safely often has to be played anyway; when it does, prefer leaving a blot where the computer needs an exact number to hit it.
Moving through the levels
Easy picks at random among plays that come close to its best, so it leaves blots open and misses hits; it is the place to practise making points and counting shots. Medium always plays its best move as it sees the board, and punishes a careless blot. Hard looks a roll further ahead: for each of its best plays it rolls all twenty-one of your replies, so it rarely leaves a direct shot it doesn't have to and hits whenever the return shots are few. The way to beat it is patience: build points in order, keep an anchor, and race only when the count is in your favour. Undo is there for learning, so use it to replay a turn and see what a different pair of moves would have done.
