Openings
What is a ECO in chess?
- Opening
- Plans
- Move Order
ECO is a chess abbreviation. In practical terms, it refers to the Encyclopaedia of Chess Openings (ECO), a standard and comprehensive chess opening reference. Also ECO code, a classification system for openings that assigns an alphanumeric code from A00 to E99 to each opening. If you see it in a database, book, or tournament page, treat it as shorthand and check the surrounding context.
What to look for on the board
- Development, center control, and king safety.
- The pawn break each side wants.
- Whether a move creates a familiar structure.
Related terms
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