Editing Rules of chess (section)

===Movement===

====Basic moves====
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{{Chess diagram small
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| Moves of the king
|  |  |  |  |  |  |  |
|  |  |  |  |  |  |  |
|  |  |  |  |oo|oo|oo|
|  |  |  |  |oo|kl|oo|
|  |  |  |  |oo|oo|oo|
|  |  |  |  |  |  |  |
|  |  |  |  |  |  |  |
|  |  |  |  |  |  |  |
}}
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| Moves of a rook
|  |  |  |oo|  |  |  |
|  |  |  |oo|  |  |  |
|  |  |  |oo|  |  |  |
|oo|oo|oo|rl|oo|oo|oo|oo
|  |  |  |oo|  |  |  |
|  |  |  |oo|  |  |  |
|  |  |  |oo|  |  |  |
|  |  |  |oo|  |  |  |

}}
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{{Chess diagram small
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| Moves of a bishop
|oo|  |  |  |  |  |oo|
|  |oo|  |  |  |oo|  |
|  |  |oo|  |oo|  |  |
|  |  |  |bl|  |  |  |
|  |  |oo|  |oo|  |  |
|  |oo|  |  |  |oo|  |
|oo|  |  |  |  |  |oo|
|  |  |  |  |  |  |  |oo

}}
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| Moves of the queen
|  |  |  |oo|  |  |  |oo
|oo|  |  |oo|  |  |oo|
|  |oo|  |oo|  |oo|  |
|  |  |oo|oo|oo|  |  |
|oo|oo|oo|ql|oo|oo|oo|oo
|  |  |oo|oo|oo|  |  |
|  |oo|  |oo|  |oo|  |
|oo|  |  |oo|  |  |oo|

}}
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 {{Chess diagram small
| tright
| Moves of a knight
|  |  |  |  |  |  |  |
|  |  |  |  |  |  |  |
|  |  |oo|  |oo|  |  |
|  |oo|  |  |  |oo|  |
|  |  |  |nl|  |  |  |
|  |oo|  |  |  |oo|  |
|  |  |oo|  |oo|  |  |
|  |  |  |  |  |  |  |

}}
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| Moves of a pawn
|  |  |  |  |  |  |  |
|  |rd|oo|rd|  |  |  |
|  |  |pl|  |  |  |  |
|  |  |  |  |  |  |  |
|  |  |  |  |oo|  |  |
|  |  |  |  |oo|  |  |
|  |  |  |  |pl|  |  |
|  |  |  |  |  |  |  |
| The pawns can move to the squares in front of them (white dots). The pawn on c6 can also take either black rook.}}
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Each type of chess piece has its own method of movement. A piece moves to a vacant square except when {{chessgloss|capturing}} an opponent's piece.{{sfn|FIDE|2023|loc=articles 3.1 and 3.1.1}}

Except for any move of the knight and [[#Castling|castling]], pieces cannot jump over other pieces. A piece is ''captured'' (or ''taken'') when an attacking enemy piece replaces it on its square. The captured piece is thereby permanently removed from the game.{{efn|When [[promotion (chess)|promoting]] a pawn, a piece previously captured and removed from the board is often used as the "new" promoted piece. The new piece is nevertheless regarded as distinct from the original captured piece; the physical piece is used simply for convenience. Moreover, the player's choice for promotion is not restricted to pieces that were previously captured.{{sfn|FIDE|2023|loc=articles 3.7.3.3 and 3.7.3.4}}}} The king can be put in [[check (chess)|check]] but cannot be captured (see below).
* The [[King (chess)|king]] moves exactly one square adjacent to it. A special move with the king known as ''[[#Castling|castling]]'' is allowed only once per player, per game (see below).
* A [[Rook (chess)|rook]] moves any number of vacant squares horizontally or vertically. It also is moved when castling.
* A [[Bishop (chess)|bishop]] moves any number of vacant squares diagonally. (Thus a bishop can move to only light or dark squares, not both.)
* The [[Queen (chess)|queen]] moves any number of vacant squares horizontally, vertically, or diagonally.
* A [[Knight (chess)|knight]] moves to one of the nearest squares not on the same {{chessgloss|rank}}, {{chessgloss|file}}, or {{chessgloss|diagonal}}. (This can be thought of as moving two squares horizontally then one square vertically, or moving one square horizontally then two squares vertically—i.e. in an "L" pattern.) The knight is not blocked by other pieces; it jumps to the new location.
* [[Pawn (chess)|Pawns]] have the most complex rules of movement:
:* A pawn moves straight forward one square, if that square is vacant. If it has not yet moved, a pawn also has the option of moving {{em|two}} squares straight forward, provided both squares are vacant. Pawns cannot move backwards.
:* A pawn, unlike other pieces, captures differently from how it moves. A pawn can capture an enemy piece on either of the two squares diagonally in front of the pawn. It cannot move to those squares when vacant except when capturing ''en passant''.
: The pawn is also involved in the two special moves [[#En passant|''en passant'']] and [[#Promotion|promotion]].<ref>{{Harvcol|Schiller|2003|pp=17–19}}</ref>
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====Castling====
{{Main|Castling}}
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{{Chess diagram small
|tright
|
|rd|  |  |  |kd|  |  |
|  |  |  |  |  |  |  |
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|  |  |  |  |  |  |  |
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|  |  |  |  |kl|  |  |rl
|Position of pieces before castling
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{{Chess diagram small
| tright
|
|  |  |kd|rd|  |  |  |
|  |  |  |  |  |  |  |
|  |  |  |  |  |  |  |
|  |  |  |  |  |  |  |
|  |  |  |  |  |  |  |
|  |  |  |  |  |  |  |
|  |  |  |  |  |  |  |
|  |  |  |  |  |rl|kl|
| Positions of the king and rook after kingside (White) and queenside (Black) castling }}
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Castling consists of moving the king two squares towards a rook, then placing the rook on the other side of the king, adjacent to it. Castling is only permissible if all of the following conditions hold:{{sfn|FIDE|2023|loc=article 3.8.2}}
* The king and rook involved in castling must not have previously moved;
* There must be no pieces between the king and the rook;
* The king may not currently be under attack, nor may the king pass through or end up in a square that is under attack by an enemy piece (though the rook is permitted to be under attack and to pass over an attacked square);
* The castling rook must be on the same rank as the king
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An unmoved king and an unmoved rook of the same color on the same rank are said to have ''castling rights''.{{sfn|FIDE|2023|loc=article 3.8.2.1}}

====''En passant''====
{{Main|En passant}}
[[File:Ajedrez captura al paso del peon.png|right|275px|alt=Three images showing ''en passant''. First, a white pawn moves from the a2-square to a4; then, the black pawn moves from b4 to a3; finally, the white pawn on a4 is removed|''en passant'']]
When a pawn advances two squares on its initial move and ends the turn adjacent to an enemy pawn on the same {{chessgloss|rank}}, it may be captured ''en passant'' by the enemy pawn as if it had moved only one square. This capture is legal only on the move immediately following the pawn's advance. The diagrams demonstrate an instance of this: if the white pawn moves from a2 to a4, the black pawn on b4 can capture it ''en passant'', moving from b4 to a3, and the white pawn on a4 is removed from the board.{{sfn|FIDE|2023|loc=articles 3.7.3.1 and 3.7.3.2}}
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====Promotion====
{{Main|Promotion (chess)}}

If a player advances a pawn to its eighth rank, the pawn is then ''promoted'' (converted) to a queen, rook, bishop, or knight of the same color at the choice of the player (a queen is most common). The choice is not limited to previously {{chessgloss|captured}} pieces. Hence it is theoretically possible for a player to have up to nine queens or up to ten rooks, bishops, or knights if all of the player's pawns are promoted.{{sfn|FIDE|2023|loc=articles 3.7.3.3, 3.7.3.4, and 3.7.3.5}}