Checkers
Authority: American Checkers Federation (ACF) Rules
Checkers, called Draughts outside North America, is played on an 8x8 board using only the 32 dark squares. Each player starts with 12 pieces on the three rows nearest them, with a dark double-corner square on their right. The darker pieces move first; the game is won by capturing or blocking all enemy pieces.
| Parameter / Specification | Standard Value | Unit |
|---|---|---|
| Total Board Squares | 64 | squares (8x8 grid) |
| Playable Squares | 32 | dark squares only |
| Pieces per Player | 12 | pieces |
History & Origin
Draughts' most likely ancestor is Alquerque, a game played on a 5x5 grid of intersecting lines that Moorish traders carried into Spain; the 1283 manuscript Libro de los Juegos, commissioned by King Alfonso X of Castile, records its rules. Sometime between the 13th and 16th centuries, European players moved the game onto the chessboard, restricting movement to the diagonals and giving rise to the checkered, forward-capturing game recognizable today -- a version already being played in southern France by around 1100.
Two French rule traditions split off from that base: le Jeu Forcé, which made capturing mandatory, and le Jeu Plaisant, which made it optional. The forced-capture tradition became the basis for the 8x8 game played in the English-speaking world as checkers or English draughts. A separate 10x10 branch, Polish draughts, emerged around 1700 and evolved into international draughts, today governed by the World Draughts Federation (FMJD) -- a different variant, on a different board size, from the 8x8 game covered here.
A Game 'Solved' by Computers
Checkers holds a distinction chess still lacks: it has been mathematically solved. In 2007, a team of Canadian computer scientists led by Jonathan Schaeffer at the University of Alberta announced they had weakly solved the game after roughly two decades of computation, proving that a game played perfectly by both sides always ends in a draw -- no forced win exists for either the darker or lighter pieces from the standard starting position.
The result didn't come from brute-force calculation of every possible game; the number of legal checkers positions (roughly 5 x 10^20) was still far too large for that. Instead, Schaeffer's team combined deep endgame databases with search algorithms that proved the outcome of the opening position without needing to resolve every branch individually, a milestone that remains one of the largest formal proofs ever completed for a popular board game.