The Encyclopedia of Chess Openings
established a classification system for openings.
Unfortunately, the classification is more thematic rather than a strict codification; this
makes it difficult to present ECO codes using traditional computing techniques. Also, after a couple of moves,
openings regularly transpose into alternative themes. The letter prefixing an opening (A-E), references one of the five volumes in the encyclopedia.
- ECO Coding
- You can follow the opening themes by ECO code
- By Move
- You can develop themes by following move sequences
- Enter an ECO code to list openings matching it
- Type all or part of a name to search for; this will find both main lines and variations