Openings

What is a MCO in chess?

  • Opening
  • Plans
  • Move Order

MCO is a chess abbreviation. In practical terms, it refers to modern Chess Openings, a popular chess opening reference. Often the edition is also given, as in MCO-14, the 14th edition. Compare ECO. 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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