Descriptive notation

Descriptive notation identifies squares relatively. Instead of always using files a, b, c, and so on, it names them after the pieces that begin there: king, queen, bishop, knight, or rook, with kingside and queenside distinctions where necessary.

Ranks are counted from the side of the player whose perspective is being used. The same physical square therefore has two names: White's QB3, the third rank of the queen bishop file, is Black's QB6. This double perspective is the central difference from algebraic notation, in which c3 is always c3.

Reading the classic example

The sequence 1. P-K4 P-K4 means 1. e4 e5. P means pawn, K means king, and K4 means the fourth square on the king file from the mover's side. Abbreviations differ across languages and publishing traditions, which adds another obstacle when reading older books.

Today the system is found mainly in historical works and older editions. The International Chess Federation (FIDE) recognizes algebraic notation for its tournaments, not descriptive notation. Converting a game is safest when each position is rebuilt move by move, because the square name depends on which color is moving.