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Openings

Theory

The body of established, analysed best moves in known openings and standard endgames.

'Theory' is the accumulated, checked-by-everyone knowledge of how specific positions should be played — the main lines of the Ruy López, the drawing method in rook endgames, and so on.

You do not need much of it to play well below master level; understanding a few structures beats memorising twenty moves you do not understand.

Why it matters

Knowing where theory ends and your own thinking must start is a practical skill in every game.

The mistake everyone makes

Memorising long opening lines without understanding the ideas, then being lost the moment the opponent deviates.

Related terms

Opening principles
The starter rules: control the centre, develop pieces, castle early, don't move the queen out too soon.
Development
Bringing your pieces off the back rank into active, useful positions.
Gambit
An opening that sacrifices material (usually a pawn) for development, the centre, or attacking chances.
Strategy
The long-term plan — where pieces belong and which structures to aim for — as opposed to tactics.

See Theory in your own games

Play the engine, train tactics, and analyse your games — ChessRanger points out these patterns as they come up so the word turns into a skill. Free to start.

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