The pawn (♙♟) is the most numerous and in most circumstances the weakest piece in the game of chess, historically representing infantry or, more particularly, armed peasants or pikemen. In chess, each player begins the game with eight pawns, one on each square of the rank immediately in front of the other pieces. (In algebraic notation, the white pawns start on a2, b2, c2, ..., h2, while black pawns start on a7, b7, c7, ..., h7.)
Individual pawns are referred to by the file on which they stand. For example, one speaks of "White's f-pawn" or "Black's b-pawn", or less commonly (using descriptive notation), "White's king's bishop pawn" or "Black's queen's knight pawn". It is also common to refer to a rook pawn, meaning any pawn on the a- or h-file, a knight pawn (on the b- or g-file), a bishop pawn (on the c- or f-file), a queen pawn (on the d-file), a king pawn (on the e-file), and a central pawn (on either the d- or e-file).
|This article uses algebraic notation to describe chess moves.|
Unlike the other pieces, pawns may not move backwards. Normally a pawn moves by advancing a single square, but the first time a pawn is moved, it has the option of advancing two squares. Pawns may not use the initial two-square advance to jump over an occupied square, or to capture. Any piece directly in front of a pawn, friend or foe, blocks its advance. In the diagram at right, the pawn on c4 may move to c5, while the pawn on e2 may move to either e3 or e4.
Unlike other pieces, the pawn does not capture in the same direction as it otherwise moves. A pawn captures diagonally, one square forward and to the left or right. In the diagram to the left, the white pawn may capture either the black rook or the black knight.
Another unusual move is the en passant capture. This arises when a pawn uses its initial move option to advance two squares instead of one, and in so doing passes over a square that is attacked by an enemy pawn. That enemy pawn, which would have been able to capture the moving pawn had it advanced only one square, is entitled to capture the moving pawn "in passing" as if it had advanced only one square. The capturing pawn moves into the empty square over which the moving pawn passed, and the moving pawn is removed from the board. In the diagram at right, the black pawn has just moved c7 to c5, so the white pawn may capture it by going from d5 to c6. The option to capture en passant must be exercised on the move immediately following the double-square pawn advance, or it is lost for the rest of the game. The en passant move was added to the pawn's repertoire in the 15th century to compensate for the then newly added two-square initial move rule (Hooper & Whyld 1992:124). Without en passant, a pawn could simply march past squares guarded by opposing pawns; en passant preserves the restrictive ability of pawns that have reached the fifth rank.
A pawn that advances all the way to the opposite side of the board (the opposing player's first rank) is promoted to another piece of that player's choice: a queen, rook, bishop, or knight of the same color. The pawn is immediately (before the opposing player's next move) replaced by the new piece. Since it is uncommon for a piece other than a queen to be chosen, promotion is often called "queening". When some other piece is chosen it is known as "underpromotion", and the piece selected is most often a knight, used to execute a checkmate or a fork giving the player a net increase in material compared to promoting to a queen. Underpromotion is also used in situations where promoting to a queen would give instant stalemate and the player chooses not to defer the promotion.[clarification needed]
The choice of promotion is not limited to pieces that have been captured. Thus a player could in theory have as many as ten knights, ten bishops, ten rooks or nine queens on the board at the same time. While this extreme would almost never occur in practice, in game 11 of their 1927 world championship match, José Raúl Capablanca and Alexander Alekhine each had two queens in play at once (from move 65 through the end on move 66). While some finer sets do include an extra queen of each color, most standard chess sets do not come with additional pieces, so the physical piece used to replace a promoted pawn on the board is usually one that was previously captured. When the correct piece is not available, some substitute is used: a second queen is often indicated by inverting a previously captured rook, or a piece is borrowed from another set.
The pawn structure, the configuration of pawns on the chessboard, mostly determines the strategic flavor of a game. While other pieces can usually be moved to a more favorable position if they are temporarily badly placed, a poorly positioned pawn is limited in its movement and often cannot be so relocated.
Because pawns capture diagonally and can be blocked from moving straight forward, opposing pawns can become locked in diagonal pawn chains of two or more pawns of each color, where each player controls squares of one color. In the diagram, Black and White have locked their d- and e-pawns.
Here, White has a long-term space advantage. White will have an easier time than Black in finding good squares for his pieces, particularly with an eye to the kingside. Black, in contrast, suffers from a bad bishop on c8, which is prevented by the black pawns from finding a good square or helping out on the kingside. On the other hand, White's central pawns are somewhat overextended and vulnerable to attack. Black can undermine the white pawn chain with an immediate c7–c5 and perhaps a later f7–f6.
Isolated pawn 
Pawns on adjacent files can support each other in attack and defense. A pawn which has no friendly pawns in adjacent files is an isolated pawn. The square in front of an isolated pawn may become an enduring weakness. Any piece placed directly in front not only blocks the advance of that pawn, but cannot be driven away by other pawns.
In the diagram at right, Black has an isolated pawn on d5. If all the pieces except the kings and pawns were removed, the weakness of that pawn might prove fatal to Black in the endgame. In the middlegame, however, Black has slightly more freedom of movement than White, and may be able to trade off the isolated pawn before an endgame ensues.
Passed pawn 
A pawn which cannot be blocked or captured by enemy pawns in its advance to promotion is a passed pawn. In the diagram at right, White has a protected passed pawn on c5 and Black has an outside passed pawn on h5. Because endgames are often won by the player who can promote a pawn first, having a passed pawn in an endgame can be decisive – especially a protected passed pawn (a passed pawn that is protected by a pawn). In this vein, a pawn majority, a greater number of pawns belonging to one player on one side of the chessboard, is strategically important because it can often be converted into a passed pawn.
The diagrammed position might appear roughly equal, because each side has a king and three pawns, and the positions of the kings are about equal. In truth, White wins this endgame on the strength of the protected passed pawn, regardless which player moves first. The black king cannot be on both sides of the board at once – to defend the isolated h-pawn and to stop White's c-pawn from advancing to promotion. Thus White can capture the h-pawn and then win the game (Fine & Benko 2003:56).
Doubled pawn 
After a capture with a pawn, a player may end up with two pawns on the same file, called doubled pawns. Doubled pawns are substantially weaker than pawns which are side by side, because they cannot defend each other, they usually cannot both be defended by adjacent pawns, and the front pawn blocks the advance of the back one. In the diagram at right, Black is playing at a strategic disadvantage due to the doubled c-pawns.
There are situations where doubled pawns confer some advantage, typically when the guarding of consecutive squares in a file by the pawns prevents an invasion by the opponent's pieces.
Pawns which are both doubled and isolated are typically a tangible weakness. A single piece or pawn in front of doubled isolated pawns blocks both of them, and cannot be easily dislodged. It is rare for a player to have three pawns in a file, i.e. tripled pawns. Depending on the position, tripled pawns may be more or less valuable than two pawns which are side by side.
Wrong rook pawn 
The pawn has its origins in the oldest version of chess, chaturanga, and it is present in all other significant versions of the game as well. In chaturanga, this piece moved directly forward, capturing to the sides (one square diagonally forward to the left or right).
In medieval chess, an attempt was made to make the pieces more interesting, each file's pawn being given the name of a commoner's occupation. On the board, from left to right, those titles were:
- Gambler and other "lowlifes", also messengers (in the left-most file, that direction being literally sinister)
- City guard or policeman (in front of a knight, as they trained city guards in real life)
- Innkeeper (bishop)
- Merchant/Moneychanger (always before the king, whether or not he is to the left or right of the queen, which depends on the color of the pieces)
- Doctor (always the queen's pawn)
- Weaver/Clerk (in front of the bishop, for whom they wove or clericked)
- Blacksmith (in front of a knight, as they care for the horses)
- Worker/Farmer (in front of a castle, for which they worked)
The most famous example of this is found in the second book ever printed in the English language, The Game and Playe of the Chesse. Purportedly, this book was viewed to be as much a political commentary on society as a chess book, and was printed by William Caxton. It was, like the Bible, among the most popular books of its day.
The ability to move two spaces, and the related ability to capture en passant, were only introduced in 15th-century Europe (see En passant#Historical context). The rule for promotion has changed through history, see Promotion (chess)#History of the rule.
Etymology and word usage 
|This section does not cite any references or sources. (January 2013)|
Although the name origin of most other chess pieces is obvious, the etymology of pawn is fairly obscure. It is derived from the Old French word paon, which comes from the Medieval Latin term for foot soldier and is a cognate to peon.
Pawn is often taken to mean "one who is easily manipulated" or "one who is sacrificed for a larger purpose". Because the pawn is the weakest piece, it is often used metaphorically to indicate unimportance or outright disposability, for example, "She's only a pawn in their game."
In most other languages, the word for pawn is similarly derived from paon or some other word for foot soldier. Exceptions are, for example, the Irish fichillín, which means little chess. The German Bauer means farmer.
- "The pawn is the soul of chess. ... the Pawns. They are the very Life of the Game. They alone form the Attack and the Defense; on their good or bad Situation depends the Gain or Loss of the Party." François-André Danican Philidor, 1749 (Euwe & Hooper 1959:1).
Unicode defines two codepoints for pawn:
♙ U+2659 White Chess Pawn (HTML ♙)
♟ U+265F Black Chess Pawn (HTML ♟)
See also 
- Brace, Edward R. (1977), An Illustrated Dictionary of Chess, Hamlyn Publishing Group, p. 213, ISBN 1-55521-394-4
- Barden, Leonard (1980), Play better chess with Leonard Barden, Octopus Books Limited, p. 11, ISBN 0-7064-0967-1
- Euwe, Max; Hooper, David (1959), A Guide to Chess Endings, Dover (1976 reprint), ISBN 0-486-23332-4
- Fine, Reuben; Benko, Pal (2003), Basic Chess Endings (1941) (revised ed.), McKay, ISBN 0-8129-3493-8
- Hooper, David; Whyld, Kenneth (1992), "en passant", The Oxford Companion to Chess (2nd ed.), Oxford University Press, ISBN 0-19-280049-3