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This page is based on the '''[https://handbook.fide.com/chapter/E012018 FIDE Handbook Laws of chess]'''.
 
== The nature and objectives of the game of chess ==

The game of chess is played between two opponents who move their pieces on a square board.

The player with the light-coloured pieces (White) makes the first move, then the players move alternately, with the player with the dark-coloured pieces (Black) making the next move.

The objective of each player is to place the opponent’s king ‘under attack’ in such a way that the opponent has no legal move. The player who achieves this goal is said to have ‘checkmated’ the opponent’s king and has won the game. The following are not allowed: 
* leaving one’s own king under attack,
* exposing one’s own king to attack,
* moving one's king over a threatened square.

If the position is such that neither player can possibly checkmate the opponent’s king, the game is drawn (either by "stalemate", if no legal move is possible, or by "insufficient material").
 
== Setup ==

{{infoBoxes3 |maxWidth=440
|title1=Starting position of the pieces on the chessboard
|body1=<center>{{chessboard
| a8={{blackRook}}  | b8={{blackKnight}}| c8={{blackBishop}}| d8={{blackQueen}} | e8={{blackKing}}  | f8={{blackBishop}}| g8={{blackKnight}}| h8={{blackRook}}
| a7={{blackPawn}}  | b7={{blackPawn}}  | c7={{blackPawn}}  | d7={{blackPawn}}  | e7={{blackPawn}}  | f7={{blackPawn}}  | g7={{blackPawn}}  | h7={{blackPawn}}
| a6=               | b6=               | c6=               | d6=               | e6=               | f6=               | g6=               | h6=               
| a5=               | b5=               | c5=               | d5=               | e5=               | f5=               | g5=               | h5=               
| a4=               | b4=               | c4=               | d4=               | e4=               | f4=               | g4=               | h4=               
| a3=               | b3=               | c3=               | d3=               | e3=               | f3=               | g3=               | h3=               
| a2={{whitePawn}}  | b2={{whitePawn}}  | c2={{whitePawn}}  | d2={{whitePawn}}  | e2={{whitePawn}}  | f2={{whitePawn}}  | g2={{whitePawn}}  | h2={{whitePawn}}
| a1={{whiteRook}}  | b1={{whiteKnight}}| c1={{whiteBishop}}| d1={{whiteQueen}} | e1={{whiteKing}}  | f1={{whiteBishop}}| g1={{whiteKnight}}| h1={{whiteRook}}
}}</center>

|title2=Piece symbols
|body2=<div style="display:grid;place-items:center;grid-template-columns:repeat(3,max-content);">
<div>King</div>
<div>{{whiteKing}}</div>
<div>{{blackKing}}</div>
<div>Queen</div>
<div>{{whiteQueen}}</div>
<div>{{blackQueen}}</div>
<div>Rook</div>
<div>{{whiteRook}}</div>
<div>{{blackRook}}</div>
<div>Bishop</div>
<div>{{whiteBishop}}</div>
<div>{{blackBishop}}</div>
<div>Knight</div>
<div>{{whiteKnight}}</div>
<div>{{blackKnight}}</div>
<div>Pawn</div>
<div>{{whitePawn}}</div>
<div>{{blackPawn}}</div>
</div>
|title3=Definitions
|body3=
'''File''': Vertical column of squares.

'''Rank''': Horizontal row of squares.

'''Diagonal''': A straight line of squares of the same colour, running from one edge of the board to an adjacent edge.
}}
== The moves of the pieces ==

* It is not permitted to move a piece to a square occupied by a piece of the same colour.
* If a piece moves to a square occupied by an opponent’s piece the latter is captured and removed from the chessboard as part of the same move.
* ''A piece is said to attack an opponent’s piece if the piece could make a capture on that square.''
* ''A piece is considered to attack a square even if this piece is constrained from moving to that square because it would then leave or place the king of its own colour under attack.''
* ''Only knights may move over any intervening pieces.''

{{InfoBoxes3 |maxWidth=440
|title1=Bishop
|body1=The bishop may move to any square along a '''diagonal''' on which it stands.
<center>{{chessboard
|e4={{blackBishop}}
|highlighta8=#0f04
|highlightb7=#0f04
|highlightc6=#0f04
|highlightd5=#0f04
|highlightf3=#0f04
|highlightg2=#0f04
|highlighth1=#0f04
|highlightb1=#0f04
|highlightc2=#0f04
|highlightd3=#0f04
|highlightf5=#0f04
|highlightg6=#0f04
|highlighth7=#0f04
}}</center>

|title2=Rook
|body2=The rook may move to any square along the '''file''' or the '''rank''' on which it stands.
<center>{{chessboard 
|d3={{blackRook}}
|highlightd8=#0f04
|highlightd7=#0f04
|highlightd6=#0f04
|highlightd5=#0f04
|highlightd4=#0f04
|highlightd2=#0f04
|highlightd1=#0f04
|highlighta3=#0f04
|highlightb3=#0f04
|highlightc3=#0f04
|highlighte3=#0f04
|highlightf3=#0f04
|highlightg3=#0f04
|highlighth3=#0f04
}}</center>

|title3=Queen
|body3=The queen may move to any square along the '''file''', the '''rank''' or a '''diagonal''' on which it stands.
<center>{{chessboard
|e4={{blackQueen}}
|highlighta8=#0f04
|highlightb7=#0f04
|highlightc6=#0f04
|highlightd5=#0f04
|highlightf3=#0f04
|highlightg2=#0f04
|highlighth1=#0f04
|highlightb1=#0f04
|highlightc2=#0f04
|highlightd3=#0f04
|highlightf5=#0f04
|highlightg6=#0f04
|highlighth7=#0f04
|highlighte8=#0f04
|highlighte7=#0f04
|highlighte6=#0f04
|highlighte5=#0f04
|highlighte3=#0f04
|highlighte2=#0f04
|highlighte1=#0f04
|highlighta4=#0f04
|highlightb4=#0f04
|highlightc4=#0f04
|highlightd4=#0f04
|highlightf4=#0f04
|highlightg4=#0f04
|highlighth4=#0f04
}}</center>
}}

{{infoBoxes3 |maxWidth=440 |colorA=#00c |colorB=#037 |colorC=#073 |colorD=#0c0 |colorE=#370
|title1=Knight
|body1=The knight may move to one of the '''squares nearest''' to that on which it stands but '''not on the same rank, file or diagonal'''.
<center>{{chessboard
|f8={{blackBishop}}
|g8={{blackKnight}}
|h8={{blackRook}}
|f7={{blackPawn}}
|g7={{blackPawn}}
|h7={{blackPawn}}
|highlighte7=#0f04
|highlightf6=#0f04
|highlighth6=#0f04

|c3={{whiteKnight}}
|highlightb1=#00f4
|highlighta2=#00f4
|highlighta4=#00f4
|highlightb5=#00f4
|highlightd5=#00f4
|highlighte4=#00f4
|highlighte2=#00f4
|highlightd1=#00f4
}}</center>

|title2=Pawn
|body2=The pawn may move:
* forward to the square immediately in front of it on the same file, provided that this square is unoccupied, or
* ''on its first move only'' the pawn may also advance two squares along the same file, provided that both squares are unoccupied, or
* the pawn may move to a square occupied by an opponent’s piece diagonally in front of it on an adjacent file, capturing that piece.

<center>{{chessboard
|b2={{whitePawn}}
|highlighta3=#f004
|highlightc3=#f004
|highlightb3=#00f4
|highlightb4=#00f4

|g5={{blackPawn}}
|highlightf4=#f004
|highlighth4=#f004
|highlightg4=#0f04
}}</center>

|title3=En passant
|body3=A pawn occupying a square on the same rank as and on an adjacent file to an opponent’s pawn which has just advanced two squares in one move from its original square may capture this opponent’s pawn as though the latter had been moved only one square. This capture is only legal on the move following this advance and is called an ‘en passant’ capture.
<center>{{chessboard
|d5={{whitePawn}}
|highlighte6=#f004

|e7={{blackPawn}}
|highlighte5=#0f04
}}</center>
}}

==== Promotion ====

When a player, having the move, plays a pawn to the rank furthest from its starting position, they must exchange that pawn as part of the same move for a new queen, rook, bishop or knight of the same colour on the intended square of arrival. This is called the square of ‘promotion’.
* The player's choice is not restricted to pieces that have been captured previously.
* This exchange of a pawn for another piece is called promotion, and the effect of the new piece is immediate.
{{InfoBoxes |maxWidth=880 |colorA=#0c0 |colorB=#370 |colorC=#730 |colorD=#c00
|title1=King
|body1=There are two different ways of moving the king:
* by moving to an adjoining square, or
* (once in the game) by ‘castling’.
{{chessboard
|c3={{whiteKing}}
|highlightb2=#00f4
|highlightb3=#00f4
|highlightb4=#00f4
|highlightc2=#00f4
|highlightc4=#00f4
|highlightd2=#00f4
|highlightd3=#00f4
|highlightd4=#00f4

|e8={{blackKing}}
|highlightd8=#0f04
|highlightd7=#0f04
|highlighte7=#0f04
|highlightf8=#0f04
|highlightf7=#0f04
}}

|title2=Castling
|body2=This is a move of the king and either rook of the same colour along the player’s first rank, counting as a single move of the king and executed as follows: the king is transferred from its original square two squares towards the rook on its original square, then that rook is transferred to the square the king has just crossed.
<div style="display:flex;flex-flow:row wrap;justify-content:space-between;">
<div style="display:flex;flex-flow:row wrap;justify-content:space-between;">
<div style="display:grid;grid-template-rows:auto-fit;place-items:center;">
<div>'''Before black queenside castling'''</div>
<div>{{chessboard
|e1={{whiteKing}}
|h1={{whiteRook}}
|e8={{blackKing}}
|a8={{blackRook}}
}}</div>
<div>'''Before white kingside castling'''</div>
</div>
<div style="display:grid;grid-template-rows:auto-fit;place-items:center;">
<div>'''After black queenside castling'''</div>
<div>{{chessboard
|g1={{whiteKing}}
|f1={{whiteRook}}
|c8={{blackKing}}
|d8={{blackRook}}
}}</div>
<div>'''After white kingside castling'''</div>
</div>
</div><div>
The right to castle has been lost:
* if the king has already moved, or
* with a rook that has already moved.
</div><div>
Castling is prevented temporarily:
* if the square on which the king stands, or the square which it must cross, or the square which it is to occupy, is attacked by one or more of the opponent's pieces, or
* if there is any piece between the king and the rook with which castling is to be effected.
</div>
</div>}}

==== Check ====

* The king is said to be 'in check' if it is attacked by one or more of the opponent's pieces, even if such pieces are constrained from moving to the square occupied by the king (because they would then leave or place their own king in check).
* '''No piece can be moved that will either expose the king of the same colour to check or leave that king in check.'''

== Game end ==

The game is won by the player:
* who has checkmated their opponent’s king.
* whose opponent declares they resign.

The game is drawn when:
* the player to move has no legal move and their king is not in check. The game is said to end in ‘stalemate’.
* a position has arisen in which neither player can checkmate the opponent’s king with any series of legal moves. The game is said to end in a ‘dead position’.
* there is agreement between the two players during the game, provided both players have made at least one move.

== Variant: Chess960 ==

Before a Chess960 game a starting position is randomly set up, subject to certain rules. After this, the game is played in the same way as regular chess. In particular, pieces and pawns have their normal moves, and each player's objective is to checkmate the opponent's king.

=== Starting position ===

The starting position for Chess960 must meet certain rules. White pawns are placed on the second rank as in regular chess. All remaining white pieces are placed randomly on the first rank, but with the following restrictions:
* the king is placed somewhere between the two rooks, and
* the bishops are placed on opposite-coloured squares, and
* the black pieces are placed opposite the white pieces.

There are 960 unique possible starting positions.

=== Chess960 castling rules ===

Chess960 allows each player to castle once per game, a move by potentially both the king and rook in a single move. However, a few interpretations of regular chess rules are needed for castling, because the regular rules presume initial locations of the rook and king that are often not applicable in Chess960.

In Chess960, depending on the pre-castling position of the castling king and rook, the castling manoeuvre is performed by one of these four methods:
# double-move castling: by making a move with the king and a move with the rook, or
# transposition castling: by transposing the position of the king and the rook, or
# king-move-only castling: by making only a move with the king, or
# rook-move-only castling: by making only a move with the rook.

==== Clarification ====

===== c-side castling =====

After c-side castling (notated as 0-0-0 and known as castling long, or queenside castling in orthodox chess), the king is on the c-square (c1 for white and c8 for black) and the rook is on the d-square (d1 for white and d8 for black).

===== g-side castling =====

After g-side castling (notated as 0-0 and known as castling short or kingside castling in orthodox chess), the king is on the g-square (g1 for white and g8 for black) and the rook is on the f-square (f1 for white and f8 for black).

In some starting positions:
* the king or rook (but not both) does not move during castling.
* castling can take place as early as the first move.

All the squares between the king's initial and final squares (including the final square) and all the squares between the rook's initial and final squares (including the final square) must be vacant except for the king and castling rook.

In some starting positions, some squares can stay filled during castling that would have to be vacant in regular chess. For example, after c-side castling (0-0-0), it is possible to have a, b, and/or e still filled, and after g-side castling (0-0), it is possible to have e and/or h filled.

== Glossary of terms in the Laws of Chess ==

'''adjourn''': Instead of playing the game in one session it is temporarily halted and then continued at a later time.

'''algebraic notation''': Recording the moves using a-h and 1-8 on the 8x8 board.

'''analyse''': Where one or more players make moves on a board to try to determine what is the best continuation.

'''arbiter''': The person(s) responsible for ensuring that the rules of a competition are followed.

'''attack''': A piece is said to attack an opponent’s piece if the player’s piece can make a capture on that square.

'''black''': There are 16 dark-coloured pieces and 32 squares called black.  When capitalised, this also refers to the player of the black pieces.

'''blitz''': A game where each player’s thinking time is 10 minutes or less.

'''board''': Short for chessboard.

'''Bronstein mode''': See delay mode.

'''capture''': Where a piece is moved from its square to a square occupied by an opponent’s piece, the latter is removed from the board.

'''castling''': A move of the king towards a rook. See [[#Castling|castling]] above. In notation 0-0 kingside castling, 0-0-0 queenside castling.

'''check''': Where a king is attacked by one or more of the opponent’s pieces. In notation +.

'''checkmate''': Where the king is attacked and cannot parry the threat. In notation ++ or #.

'''chessboard''': The 8x8 grid. See [[#The_initial_position_of_the_pieces_on_the_chessboard|The initial position of the pieces on the chessboard]] above.

'''chess clock''': A clock with two time displays connected to each other.

'''chess set''': The 32 pieces on the chessboard.

'''Chess960''': A variant of chess where the back-row pieces are set up in one of the 960 distinguishable possible positions.

'''clock''': One of the two time displays.

'''cumulative (Fischer) mode''': Where a player receives an extra amount of time (often 30 seconds) prior to each move.

'''dead position''': Where neither player can mate the opponent’s king with any series of legal moves.

'''default time''': The specified time a player may be late without being forfeited.

'''delay (Bronstein) mode''': Both players receive an allotted ‘main thinking time’. Each player also receives a ‘fixed extra time’ with every move. The countdown of the main thinking time only commences after the fixed extra time has expired. Provided the player presses their clock before the expiration of the fixed extra time, the main thinking time does not change, irrespective of the proportion of the fixed extra time used.

'''diagonal''': A straight line of squares of the same colour, running from one edge of the board to an adjacent edge.

'''draw''': Where the game is concluded with neither side winning.

'''draw offer''': Where a player may offer a draw to the opponent. This is indicated on the scoresheet with the symbol (=).

'''en passant''': see [[#En_passant|en passant]] above.

'''exchange''': Where a pawn is promoted. Or where a player captures a piece of the same value as their own and this piece is recaptured. Or where one player has lost a rook and the other has lost a bishop or knight.

'''explanation''': A player is entitled to have a Law explained.

'''fair play''': Whether justice has been done has sometimes to be considered when an arbiter finds that the Laws are inadequate.

'''file''': A vertical column of eight squares on the chessboard.

'''Fischer mode''': See cumulative mode.

'''flag''': The device that displays when one player's alotted time has completely expired. Also, to win on time, i.e., because the opponent's time expired. ("They flagged their opponent.")

'''flag-fall''': Where the allotted time of a player has expired.

'''forfeit''': To lose the right to make a claim or move. Or 2. To lose a game because of an infringement of the Laws.

'''illegal''': A position or move that is impossible because of the Laws of Chess.

'''increment''': An amount of time (from 2 to 60 seconds) added from the start before each move for the player. This can be in either delay or cumulative mode.

'''insufficient material''': Not having enough pieces to checkmate. A pawn can be promoted, e.g., to a queen, but a single knight or bishop is not enough to checkmate. If both players have insufficient material, or if one player wins on time but has insufficient material, the game is drawn.

'''kingside''': The vertical half of the board on which the king stands at the start of the game.

'''made''': A move is said to have been ‘made’ when the piece has been moved to its new square, the hand has quit the piece, and the captured piece, if any, has been removed from the board.

'''mate''': Abbreviation of checkmate.

'''minor piece''': Bishop or knight.

'''move''': 40 moves in 90 minutes, refers to 40 moves by each player. Or having the move refers to the player’s right to play next. Or White’s best move refers to the single move by White.

'''move-counter''': A device on a chessclock which may be used to record the number of times the clock has been pressed by each player.

'''normal means''': Playing in a positive manner to try to win, or having a position such that there is a realistic chance of winning the game other than just flag-fall.

'''over-the-board''': The Laws cover only this type of chess, not internet, nor correspondence, and so on.

'''piece''': One of the 32 figurines on the board. Or a queen, rook, bishop or knight.

'''press the clock''': The act of pushing the button or lever on a chess clock which stops the player’s clock and starts that of their opponent.

'''promotion''': Where a pawn reaches the eighth rank and is replaced by a new queen, rook, bishop or knight of the same colour.

'''queen''': As in queen a pawn, meaning to promote a pawn to a queen.

'''queenside''': The vertical half of the board on which the queen stands at the start of the game.

'''quickplay finish''': The last part of a game where a player must complete an unlimited number of moves in a finite time.

'''rank''': A horizontal row of eight squares on the chessboard.

'''rapid chess''': A game where each player’s thinking time is more than 10 minutes, but less than 60.

'''repetition''': A player may claim a draw if the same position occurs three times. A game is drawn if the same position occurs five times.

'''resigns''': Where a player gives up, rather than play on until mated.

'''result''': Usually the result is 1-0, 0-1 or ½-½. In exceptional circumstances both players may lose (Article 11.8), or one score ½ and the other 0. For unplayed games the scores are indicated by +/- (White wins by forfeit), -/+ (Black wins by forfeit), -/- (Both players lose by forfeit).

'''sealed move''': Where a game is adjourned the player seals their next move in an envelope.

'''scoresheet''': A paper sheet with spaces for writing the moves. This can also be electronic.

'''screen''': An electronic display of the position on the board.

'''spectators''': People other than arbiters or players viewing the games. This includes players after their games have been concluded.

'''standard chess''': A game where each player’s thinking time is at least 60 minutes.

'''stalemate''': Where the player has no legal move and their king is not in check.

'''square of promotion''': The square a pawn lands on when it reached the eighth rank.

'''time control''': The regulation about the time the player is allotted. For example, 40 moves in 90 minutes, all the moves in 30 minutes, plus 30 seconds cumulatively from move 1. Or a player is said ‘to have reached the time control’, if, for example they have completed the 40 moves in less than 90 minutes.

'''time period''': A part of the game where the players must complete a number of moves or all the moves in a certain time.

'''vertical''': The 8th rank is often thought as the highest area on a chessboard. Thus each file is referred to as ‘vertical’.

'''white''': There are 16 light-coloured pieces and 32 squares called white. When capitalised, this also refers to the player of the white pieces.

'''50-move rule''': A player may claim a draw if the last 50 moves have been completed by each player without the movement of any pawn and without any capture.

'''75-move rule''': The game is drawn if the last 75 moves have been completed by each player without the movement of any pawn and without any capture.