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Chess glossary: terms you can apply on the board
Look up chess terms with short, practical explanations. Each entry connects the definition to decisions you make during a real game, not just abstract theory.
30 matching lessons
Advanced Algebraic Notation in Chess: Meaning and Examples
Reconstruct Advanced Algebraic Notation from a position reconstructed from notation; preserve the state fields and test what the record cannot tell you.
TacticsBlunder, Mistake, or Inaccuracy in Chess?
Understand the practical difference between a blunder, mistake, and inaccuracy, why engine labels vary, how errors happen, and how to review the first cause.
TrainingChess Calculation and Visualization
Learn a practical chess calculation process: generate candidates, test forcing replies, visualize positions, stop at stable points, evaluate, and train accurately.
NotationCheckmate in Notation in Chess: Meaning and Examples
Reconstruct Checkmate in Notation from a position reconstructed from notation; preserve the state fields and test what the record cannot tell you.
NotationChess Engine Centipawns in Chess: Meaning and Examples
Reconstruct Chess Engine Centipawns from the legal-move test; preserve the state fields and test what the record cannot tell you.
NotationChess Rating Vocabulary in Chess: Meaning and Examples
Reconstruct Chess Rating Vocabulary from the legal-move test; preserve the state fields and test what the record cannot tell you.
NotationChess Repertoire Definition in Chess: Meaning and Examples
Reconstruct Chess Repertoire Definition from the legal-move test; preserve the state fields and test what the record cannot tell you.
NotationECO Opening Codes in Chess: Meaning and Examples
Reconstruct ECO Opening Codes from the legal-move test; preserve the state fields and test what the record cannot tell you.
NotationFEN Active Color Field in Chess: Meaning and Examples
Reconstruct FEN Active Color Field from the legal-move test; preserve the state fields and test what the record cannot tell you.
NotationFEN Castling Field in Chess: Meaning and Examples
Reconstruct FEN Castling Field from castling rights stored in FEN; preserve the state fields and test what the record cannot tell you.
NotationFEN Piece Placement in Chess: Meaning and Examples
Reconstruct FEN Piece Placement from the legal-move test; preserve the state fields and test what the record cannot tell you.
StrategyWhat Is a Fianchetto in Chess?
Learn how a fianchetto develops a bishop to g2, b2, g7, or b7; understand long-diagonal control, pawn structure, king safety, attacking plans, and trade-offs.
NotationFullmove Number in FEN in Chess: Meaning and Examples
Reconstruct Fullmove Number in FEN from the legal-move test; preserve the state fields and test what the record cannot tell you.
OpeningsWhat Is a Gambit in Chess?
Understand chess gambits: compensation types, when to accept or decline, and links to practical gambit openings on 1chess.online.
NotationGlicko versus Elo in Chess: Meaning and Examples
Reconstruct Glicko versus Elo from the legal-move test; preserve the state fields and test what the record cannot tell you.
NotationHalfmove Clock in FEN in Chess: Meaning and Examples
Reconstruct Halfmove Clock in FEN from the legal-move test; preserve the state fields and test what the record cannot tell you.
StrategyThe Initiative in Chess: Create and Convert Pressure
Learn what the initiative means, how forcing threats gain time, how development and king safety create it, when to sacrifice for it, and how to convert or neutralize it.
NotationLong Algebraic Notation in Chess: Meaning and Examples
Reconstruct Long Algebraic Notation from a position reconstructed from notation; preserve the state fields and test what the record cannot tell you.
NotationOpening Transposition in Chess: Meaning and Examples
Reconstruct Opening Transposition from the legal-move test; preserve the state fields and test what the record cannot tell you.
EndgamesOpposition in Chess King Endgames
Learn direct, distant, and diagonal opposition, connect it to key squares and zugzwang, understand when side to move matters, and practise king-and-pawn endings.
EndgamesPassed Pawns: Create, Push, and Stop Them
Learn what makes a pawn passed, the difference between protected, connected, and outside passers, when to push, how to blockade, and where kings and rooks belong.
NotationPGN Movetext in Chess: Meaning and Examples
Reconstruct PGN Movetext from the legal-move test; preserve the state fields and test what the record cannot tell you.
NotationPGN Tag Pairs in Chess: Meaning and Examples
Reconstruct PGN Tag Pairs from the legal-move test; preserve the state fields and test what the record cannot tell you.
NotationPrincipal Variation in Chess: Meaning and Examples
Reconstruct Principal Variation from the legal-move test; preserve the state fields and test what the record cannot tell you.
StrategyProphylaxis in Chess: Prevent the Opponent's Plan
Learn prophylactic thinking: identify the opponent's plan, prevent useful breaks and piece routes, improve your position, and avoid passive over-defense.
NotationStandard Algebraic Notation in Chess: Meaning and Examples
Reconstruct Standard Algebraic Notation from a position reconstructed from notation; preserve the state fields and test what the record cannot tell you.
StrategyTempo in Chess: How Move-Time Shapes the Position
Learn what a tempo means in chess, how to gain or lose time through development and threats, when repeated moves are justified, and how reserve tempi decide endings.
NotationUCI Move Notation in Chess: Meaning and Examples
Reconstruct UCI Move Notation from a position reconstructed from notation; preserve the state fields and test what the record cannot tell you.
NotationWhat Is a Chess Ply in Chess: Meaning and Examples
Reconstruct What Is a Chess Ply from the legal-move test; preserve the state fields and test what the record cannot tell you.
EndgamesZugzwang in Chess: When Every Move Makes Things Worse
Learn what zugzwang means, why passing would help, how it appears in pawn and piece endings, how reserve tempi and triangulation create it, and how to recognize it.