Chess glossary

Chess has its own vocabulary. Here are the terms you will hear most often, explained in plain words, from algebraic notation to zugzwang.

Algebraic notation

The standard way to write chess moves. Files are a to h, ranks 1 to 8, and pieces are K, Q, R, B, N (pawns have no letter). Nf3 means a knight moves to f3.

Blunder

A very bad move that loses material or the game, often marked ?? in notation.

Castling

A move of the king and a rook together. Written O-O for kingside and O-O-O for queenside.

Center

The four squares e4, d4, e5 and d5, and the squares around them.

Check

An attack on the king. The player in check must escape it on the next move.

Checkmate

A check that cannot be escaped. It ends the game. Written with # in notation.

Development

Moving pieces from their starting squares to active squares in the opening.

Discovered attack

Moving one piece to reveal an attack by another piece behind it.

Double check

Check from two pieces at once. The only escape is to move the king.

Draw

A game with no winner. Caused by stalemate, agreement, repetition, the 50-move rule or insufficient material.

Elo rating

A number that measures playing strength. Beginners are often 400 to 1000; grandmasters are usually above 2500.

En passant

A special pawn capture of a pawn that just moved two squares and landed beside it.

Endgame

The final phase of the game, when few pieces are left and kings become active.

Exchange

Trading pieces of equal value. Winning the exchange means trading a bishop or knight for a rook.

FEN

Forsyth-Edwards Notation: one line of text that describes a whole chess position.

Fianchetto

Developing a bishop to b2, g2, b7 or g7 after moving the pawn in front of it one square.

File

A vertical column of squares, named a to h. An open file has no pawns on it.

Fork

One piece attacking two or more enemy pieces at the same time. Knights are famous for forks.

Gambit

An opening that offers material, usually a pawn, for faster development or attack.

Hanging piece

A piece that is attacked and not defended, so it can be captured for free.

Middlegame

The phase after the opening, when plans and tactics decide most games.

Opening

The first moves of the game, when both sides develop their pieces.

Opposition

Kings facing each other with one square between them. Important in king and pawn endings.

Passed pawn

A pawn with no enemy pawns in front of it on its file or the files next to it.

PGN

Portable Game Notation: the standard text format for saving whole games. Pawnly can copy your game as PGN.

Pin

An attack on a piece that cannot move without exposing a more valuable piece behind it.

Promotion

A pawn that reaches the last rank becomes a queen, rook, bishop or knight.

Rank

A horizontal row of squares, numbered 1 to 8.

Resign

To give up the game before checkmate.

Skewer

Like a pin in reverse: a valuable piece is attacked and must move, exposing a piece behind it.

Stalemate

The side to move has no legal move and is not in check. The game is a draw.

Tempo

A unit of time, one move. Gaining a tempo means making progress while forcing your opponent to react.

Threefold repetition

If the same position occurs three times, the game can be claimed as a draw.

Zugzwang

A position where any move makes things worse, but you are not allowed to pass.