Algebraic chess notation
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Algebraic chess notation is the method used today by all competition chess organizations and most books, magazines, and newspapers to record and describe the play of chess games. The form most commonly used, and primarily described here, is also called abbreviated (or short) algebraic notation or SAN to distinguish it from the expanded (or long) algebraic notation variant now referred to as LAN. Beginning in the 1970s, the abbreviated algebraic notation eventually came to replace descriptive chess notation in English chess literature, although this notation can be found in older literature. Algebraic notation was already commonly used in other languages.
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[edit] Naming squares on the board
The notation begins by identifying each square of the chessboard with a unique coordinate. First, the files (that is, lines running parallel to the direction the players are facing) are labelled with lowercase letters a through h, from the left of the "white" player. So the "a" file is to white's left, and to black's right. Then the ranks (lines running horizontally between the players) are numbered from 1 to 8, starting from white's home rank. Thus, black's home rank is rank 8. Each square of the board, then, is uniquely identified by its file letter and rank number. The white king, for example, starts the game on square e1. The black knight on b8 can move to a6, c6 or d7 (provided the squares are vacant of other black pieces).
[edit] Naming the pieces
Each type of piece (other than pawns) is identified by an uppercase letter, usually the first letter in the name of that piece in whatever language is spoken by the player recording. English-speaking players use K for king, Q for queen, R for rook, B for bishop, and N for knight (since K is already used). S was also used for the knight in the early days of algebraic notation, from the German Springer (this is still used in chess problems, where N stands for the popular fairy chess piece, the nightrider).
Players may use different letters in other languages. For example, French players use F for bishop (from fou). In chess literature written for an international audience, the language-specific letters are replaced by universal icons for the pieces, producing Figurine notation.
Pawns are not indicated by a letter, but by the absence of such a letter—it is not necessary to distinguish between pawns for normal moves, as only one pawn can move to any one square (captures are indicated differently; see below).
[edit] Notation for moves
Each move of a piece is indicated by the piece's letter, plus the coordinate of the destination square. For example Be5 (move a bishop to e5), Nf3 (move a knight to f3), c5 (move a pawn to c5—no initial in the case of pawn moves). In some publications, the pieces are indicated by graphical representations rather than by initials: for example, ♞c6. This is called figurine algebraic notation or FAN and has the advantage of being language independent.
[edit] Notation for captures
When a piece makes a capture, an x is inserted between the initial and the destination square. For example, Bxe5 (bishop captures the piece on e5). When a pawn makes a capture, the file from which the pawn departed is used in place of a piece initial. For example, exd5 (pawn on the e-file captures the piece on d5). Sometimes when it is unambiguous, a pawn capture is indicated only by the files, e.g. exd, ed5 or ed.
A colon (:) is sometimes used instead of an x, either in the same place the x would go (B:e5) or after the move (Be5:). En passant captures (see pawn) are specified by the capturing pawn's file of departure, the x, and the square to which it moves (not the location of the captured pawn), optionally followed by the notation "e.p." It is never necessary to specify that a capture was en passant because a capture from the same file but not en passant would have a different destination square. Within the SAN (Standard Algebraic Notation) standard, the "x" capture indication is always required while the "e.p." en passant move suffix indication is always forbidden.
Some texts, such as the Encyclopedia of Chess Openings, omit indications that a capture has been made.
[edit] Disambiguating moves
If two (or more) identical pieces can move to the same square, the piece's initial is followed by (in descending order of preference):
- the file of departure if they differ;
- the rank of departure if the files are the same but the ranks differ;
- Both the file and rank if neither alone uniquely defines the piece (after a pawn promotion, if three or more of the same piece able to reach the square).
For example, with two knights on g1 and d2, either of which might move to f3, the move is indicated as Ngf3 or Ndf3, as appropriate. With two knights on g5 and g1, the moves are N5f3 or N1f3. As above, an x may be used to indicate a capture: for example, N5xf3.
[edit] Pawn promotion
If a pawn moves to its last rank, achieving promotion, the piece chosen is indicated after the move, for example e1Q, b8B. Sometimes an "=" sign or brackets are used: f8=Q or f8(Q), but neither is a FIDE standard. (The "=" sign is in fact used to represent the offer of a draw.)
[edit] Castling
Castling is indicated by the special notations 0-0 for kingside castling and 0-0-0 for queenside (note that while this is what the FIDE Handbook uses, PGN requires O-O and O-O-O instead). Optionally, it may be indicated by the king's move alone, since moving the king more than one square implies castling. For example, Kg1.
[edit] Check and checkmate
A move which places the opponent's king in check usually has the notation "+" added. Some use †. (Sometimes ch is used to indicate check.) Double check is sometimes represented "++". Checkmate can likewise be indicated "#" (some use "++" instead, but the United States Chess Federation recommends "#"). Sometimes ‡ is used. The word 'mate' written at the end of the notation is also acceptable.
[edit] End of game
The notation 1-0 at the end of the moves indicates that white won, 0-1 indicates that black won, and ½-½ indicates a draw.
[edit] Example
Moves are generally written in one of two ways.
(1) written in two columns, as a white/black pair, preceded by the move number and a period:
- 1. e4 e5
- 2. Nf3 Nc6
- 3. Bb5 a6
(2) in text: 1. e4 e5 2. Nf3 Nc6 3. Bb5 a6.
Moves may be interspersed with text. When the score resumes with a black move, an ellipsis (...) takes the place of the white move, for example:
- 1. e4 e5
- 2. Nf3
- Black now defends his pawn
- 2. ... Nc6
- 3. Bb5 a6
[edit] Endgame classification
Endgames can be classified by the material on the board. The standard classification system lists each player's material, including the kings, in the following order:king, queen, bishops, knights, rooks, pawn. Each piece is designated by its algebraic symbol.
For example, if White has a king and pawn, and Black has only a king, the endgame is classified KPK. If White has bishop and knight, and Black has a rook, the endgame is classified KBNKR. Note that KNBKR would be incorrect; bishops come before knights.
In positions with two or more bishops on the board, a "bishop signature" may be added to clarify the relationship between the bishops. Two methods have been used. The informal method is to designate one color of squares as "x" and the other color as "y". An endgame of KBPKB can be written KBPKB x-y if the bishops are opposite colored, or KBPKB x-x if the bishops are same-colored. The more formal method is to use a four digit suffix of the form abcd:
- a = number of White light-squared bishops
- b = number of White dark-squared bishops
- c = number of Black light squared bishops
- d = number of Black dark-squared bishops
Thus, the aforementioned endgame can be written KBPKB_1001 for opposite-color bishops, and KBPKB_1010 for same-color bishops.
GBR code is an alternative method of endgame classification.
[edit] Naming the pieces in various languages
Here are the piece abbreviations used in various languages:
-
Language king queen rook bishop knight figurine ♔♚ ♕♛ ♖♜ ♗♝ ♘♞ Arabic م ف ر فل حص Czech, Slovak K D V S J Danish, German, Norwegian, Slovenian, Swedish K D T L S Dutch K D T L P English K Q R B N (Kt) Esperanto R D T K Ĉ Estonian K L V O R Finnish K D T L R French R D T F C Greek Ρ Β Π Α Ι Hungarian K V B F H Icelandic K D H B R Ido R D T E K Indonesian R M B G K Italian R D T A C Latvian K D T L Z Lithuanian K V B R Ž Maltese R R T I Ż Polish K H W G S Portuguese R D T B C Romanian R D T N C Russian Кр (Kr) Ф (F) Л (L) С (S) К (K) Spanish R D T A C Swedish K D T L S Turkish Ş V K F A Welsh T B C E M Chinese 王 后 车 象 马
[edit] Similar notations
[edit] PGN
Chess games are often stored in computer files using Portable Game Notation (PGN), which uses algebraic chess notation as well as additional markings to describe a game.
[edit] Long algebraic notation
Some computer programs (and people) use a variant of algebraic chess notation, termed long algebraic notation or fully expanded algebraic notation. In fully expanded algebraic notation, moves include both the starting and ending position separated by a hyphen. Examples include "e2-e4". Notations from short algebraic notation are frequently used in long algebraic notation in such constructions as "Nb1-c3" or "Rd3xd7". This notation takes more space and thus is not as commonly used. However it has the advantage of clarity, particularly for less skilled players or players learning the game.
Some books using primarily short algebraic notation use the long notation instead of the disambiguation forms.
[edit] Numeric notation
In international correspondence chess the use of algebraic notation may cause confusion, since different languages have different names (and therefore different initials) for the pieces; hence the standard for transmitting moves in this form of chess is ICCF numeric notation.
[edit] Common shorthand notation
The following short-hand notations are frequently used to comment moves:
- ! a good move
- !! an excellent move
- ? a mistake
- ?? a blunder
- !? an interesting move that may not be best
- ?! a dubious move, but not easily refuted
- □ only move
and many others.
[edit] See also
[edit] External links
- FIDE rules on algebraic notation (see appendix E)
- notation website
