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Backgammon
Board · Classics · plays in your browser, no download
Two players, fifteen checkers each, and a race in opposite directions around the same twenty-four points. The dice decide what you may do; you decide what to do with it. That split is why a game this old has never been solved by luck alone — and why a good player beats a bad one over a session, but not reliably over one game.
Where it comes from
Backgammon belongs to a family of race games that is about as old as writing. The Royal Game of Ur, played in Mesopotamia around 2600 BC, is the oldest board game whose rules we actually have: they survive on a Babylonian tablet, written down by a scribe some two thousand years after the boards themselves were buried. Excavations at the Burnt City in south-eastern Iran turned up a board and counters dated to roughly five thousand years ago.
The Romans played tabula, a two-dice game on a board of the same shape. In Persia it was nard, which appears somewhere between the third and the sixth century AD and travelled west again with the Arab conquests. By the seventeenth century the English version had arrived at almost exactly the modern rules — two dice, doubles played twice — and had picked up the name: backgammon is usually dated to about 1645. Edmond Hoyle wrote the first serious treatise on it in 1743.
Then nothing much happened for two hundred years, and then one object changed the whole game. In the 1920s, in the gaming clubs of New York, somebody — nobody knows who — introduced the doubling cube. It is not a die. It is a running bet on who is ahead, which either player may raise and the other must either accept or resign. Overnight the question stopped being how do I win this race and became how far ahead am I, and does my opponent know it. In 1931 a committee at the New York Racquet and Tennis Club, under Wheaton Vaughan, wrote down the rules that are still the international standard.
The last chapter is a computer one. In 1992 Gerald Tesauro at IBM built TD-Gammon, a neural network that learned by playing itself hundreds of thousands of times and nothing else. It reached the level of the best humans, and then it did something stranger: it preferred some opening moves that every book called wrong. The books were changed. Backgammon is one of the very few old games where the machines did not just beat the players, they corrected them.
How to play
| The goal | Bring all fifteen of your checkers round to your own home board, then bear them off. First one out wins. |
|---|---|
| Moving | Roll two dice and move one checker by each number, or one checker twice. Roll a double and you play it four times. |
| Blocking | A point with two or more enemy checkers is shut to you. Six in a row is a prime, and nothing gets past it. |
| Hitting | A point with a single enemy checker is a blot. Land on it and that checker goes to the bar and starts again from zero. |
| The bar | While you have a checker on the bar you may do nothing else until it re-enters. |
| Bearing off | Only once every checker is home. A gammon is double, a backgammon triple. |
The doubling cube sits beside the board at 64, meaning one. Before your roll you may offer it; your opponent either takes it, at twice the stake and now owning the cube, or drops and pays one. A rule of thumb that is very nearly the real mathematics: take if you would win this position about one time in four, and drop below that.
Our version
Ten opponents, from a beginner that genuinely plays badly to one that will punish a loose blot, the doubling cube, and move-by-move analysis afterwards so you can see where the game actually turned — which is almost never where it felt like it did.
Three things that help
Leave fewer blots than you think you can afford. Beginners count the pips and play the race. Good players count the shots: how many of the thirty-six rolls hit you next turn.
Make points, not distance. Two checkers on a useful point are worth more than two checkers further along on nothing.
The cube is a skill, not a flourish. More games are thrown away by taking a double that should have been dropped than by any bad move on the board.