The Rules

Setup 

Chess is played on a square board divided into eight rows of squares called ranks and eight columns called files, with a dark square in each player's lower left corner.^[13] This is altogether 64 squares. The colors of the squares are laid out in a checker (chequer) pattern in light and dark squares. To make speaking and writing about chess easy, each square has a name. Each rank has a number from 1 to 8, and each file a letter from a to h. This means that every square on the board has its own label, such as g1 or f5. The pieces are in white and black sets. The players are called White and Black, and at the start of a game each player has 16 pieces. The 16 pieces are one king, one queen, two rooks, two bishops, two knights and eight pawns.

Movement

Definitions: vertical lines are files; horizontal lines are ranks; lines at 45° are diagonals. Each piece has its own way of moving around the board. The X marks the squares where the piece can move.

• The knight is the only piece that can jump over another piece.
• No piece may move to a square occupied by a piece of the same color.
• All pieces capture the same way they move, except pawns.

Moves of the king

Moves of the rook

Moves of the bishop

Moves of the queen

Moves of the knight

Moves of the pawn

• The king's move is one square in any direction. The king (K for short) may not move to any square where it is threatened by an opposing piece. However, the king can move to a square that is occupied by an opponent's piece and capture the piece, taking it off the board.
• The queen (Q) can move any distance in any direction on the ranks, files and diagonals.
• The rooks (R) move any distance on the ranks or files.
• The bishops (B) move diagonally on the board. Since a bishop can only move diagonally, it will always be on the same color square.
• The knights (Kt or N) move in an "L" shape. Each move must be either two squares along a rank and one square along a file, or two squares along a file and one square along a rank. It is the only piece that can jump over other pieces. Like the other pieces, it captures an opposing piece by landing on its square.
• The pawns can only move up the board. On its first move a pawn may move either one or two squares forward. A pawn captures one square diagonally, not as it moves: see white circles on its diagram. Besides, in some situations pawns can capture opponent's pawns in a special way called en passant, which means in passing in French (see below).

Capturing

Most pieces capture as they move. If a piece lands on an opponent's piece, the opposing piece is taken off the board. There are three special cases:

1. The king cannot be taken (see check and checkmate).
2. No piece can be taken while castling (see below).
3. Pawns take one square diagonally.

Check and checkmate

An example of checkmate

If a move is made which attacks the opposing king, that king is said to be 'in check'. The player whose king is checked must make a move to remove the check. The options are: moving the king, capturing the threatening piece, or moving another piece between the threatening piece and the king. If the player whose king is in danger cannot do any of these things, it is checkmate, and the player loses the game.

How a game ends

Checkmates are rare in competitive chess. The most common ends are decisions made by one or both players.

Wins

Checkmate. When a king is in check, and cannot get out of it.

• Resignation. A player may resign at any time, usually because his/her position is hopeless. A losing player is able to resign by placing their king on its side on the chessboard.
• Out of time. If player's clock time is over (exceeding the time control). Strictly speaking, this is not part of the rules of the game, but part of the rules of tournament and match chess where chess clocks are used.

Draws

Draw agreed. A game may end in a draw at any time if one player offers a draw and the other accepts.

• Dead position. A position where no series of legal moves could lead to a mate (example: K+B vs K). The game is drawn.
• Stalemate. If a player cannot make a move, and the player's king is not in check, this is also a draw. This kind of draw is called a stalemate, and is rare.^[4]
• 50-move rule. A game will also end in a draw if no piece is captured and no pawn has moved after fifty moves. This is called the fifty-move rule, and happens late in the game.^[18]
• Threefold repetition. If the exactly same position is repeated three times during a game with the same player to move each time, the player next to move may claim a draw. The game is now drawn. This is called a draw by threefold repetition.^[19]