Wikipedia all about chess
This article is about the Western board game. For other chess games or other uses, see Chess (disambiguation).
Chess
A selection of white and black chess pieces on a checkered surface.
Part of a Staunton chess set
Left to right: white king, black rook, black queen, white pawn, black knight, white bishop
Years active c. 1475 to present[1] (predecessors c. 900 years earlier)
Genres
Board game
Abstract strategy game
Mind sport
Players 2
Chance None
Skills Strategy, tactics
Synonyms
International chess
Western chess
Chess is a board game for two players. It is an abstract strategy game that involves no hidden information and no elements of chance. It is played on a square board consisting of 64 squares arranged in an 8×8 grid. The players, referred to as "White" and "Black", each control sixteen pieces: one king, one queen, two rooks, two bishops, two knights, and eight pawns, with each type of piece having a different pattern of movement. An enemy piece may be captured (removed from the board) by moving one's own piece onto the square it occupies. The object of the game is to "checkmate" (threaten with inescapable capture) the enemy king. There are also several ways a game can end in a draw.
The recorded history of chess goes back to at least the emergence of chaturanga—also thought to be an ancestor to similar games like Janggi, xiangqi and shogi—in seventh-century India. After its introduction in Persia, it spread to the Arab world and then to Europe. The modern rules of chess emerged in Europe at the end of the 15th century, with standardization and universal acceptance by the end of the 19th century. Today, chess is one of the world's most popular games, with millions of players worldwide.
Organized chess arose in the 19th century. Chess competition today is governed internationally by FIDE (Fédération Internationale des Échecs), the International Chess Federation. The first universally recognized World Chess Champion, Wilhelm Steinitz, claimed his title in 1886; Gukesh Dommaraju is the current World Champion, having won the title in 2024.
A huge body of chess theory has developed since the game's inception. Aspects of art are found in chess composition, and chess in its turn influenced Western culture and the arts, and has connections with other fields such as mathematics, computer science, and psychology. One of the goals of early computer scientists was to create a chess-playing machine. In 1997, Deep Blue became the first computer to beat a reigning World Champion in a match when it defeated Garry Kasparov. Today's chess engines are significantly stronger than the best human players and have deeply influenced the development of chess theory; however, chess is not a solved game.
This article uses algebraic notation to describe chess moves.
Rules
Main article: Rules of chess
The rules of chess are published by FIDE (Fédération Internationale des Échecs; "International Chess Federation"), chess's world governing body, in its Handbook.[2] Rules published by national governing bodies, or by unaffiliated chess organizations, commercial publishers, etc., may differ in some details. FIDE's rules were most recently revised in 2023.
Setup
Setup at the start of a chess game
Chess sets come in a wide variety of styles. The Staunton pattern is the most common, and is usually required for competition.[3] Chess sets come with pieces in two colors, referred to as white and black, regardless of their actual color; the players controlling the color sets are referred to as White and Black, respectively. Each set comes with at least the following 16 pieces in both colors: one king, one queen, two rooks, two bishops, two knights, and eight pawns.[2]
The game is played on a square board of eight rows (called ranks) and eight columns (called files). Although it does not affect gameplay, by convention the 64 squares alternate in color and are referred to as light and dark squares.[2]
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a8 black rookb8 black knightc8 black bishopd8 black queene8 black kingf8 black bishopg8 black knighth8 black rooka7 black pawnb7 black pawnc7 black pawnd7 black pawne7 black pawnf7 black pawng7 black pawnh7 black pawna2 white pawnb2 white pawnc2 white pawnd2 white pawne2 white pawnf2 white pawng2 white pawnh2 white pawna1 white rookb1 white knightc1 white bishopd1 white queene1 white kingf1 white bishopg1 white knighth1 white rook
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Initial position: first row: rook, knight, bishop, queen, king, bishop, knight, rook; second row: pawns
To start the game, White's pieces are placed on the first rank in the following order, from left to right: rook, knight, bishop, queen, king, bishop, knight, rook. Pawns are placed on each square of the second rank. Black's position mirrors White's, with equivalent pieces on every file.[2] The board is oriented so that the right-hand corner nearest each player is a light square; as a result the white queen always starts on a light square, while the black queen starts on a dark square. This may be remembered by the phrases "white on the right" and "queen on her color".[4]
In competition, the piece colors are allocated to players by the organizers. In informal games, colors may be decided either by mutual agreement, or randomly, for example by a coin toss, or by one player concealing a white pawn in one hand and a black pawn in the other and having the opponent choose.[citation needed]
Movement
White moves first, after which players alternate turns. One piece is moved per turn (except when castling, during which two pieces are moved). In the diagrams, dots mark the squares to which each type of piece can move if unoccupied by friendly pieces and there are no intervening piece(s) of either color (except the knight, which leaps over any intervening pieces). With the sole exception of en passant, a piece captures an enemy piece by moving to the square it occupies, removing it from play and taking its place. The pawn is the only piece that does not capture the way it moves, and it is the only piece that moves and captures in only one direction (forwards from the player's perspective). A piece is said to control empty squares on which it could capture, attack squares with enemy pieces it could capture, and defend squares with pieces of the same color on which it could recapture. Moving is compulsory; a player may not skip a turn, even when having to move is detrimental.
Moves of the king
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Moves of a rook
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Moves of a bishop
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h8 white circlea7 white circleg7 white circleb6 white circlef6 white circlec5 white circlee5 white circled4 white bishopc3 white circlee3 white circleb2 white circlef2 white circlea1 white circleg1 white circle
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Moves of a queen
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d8 white circleh8 white circlea7 white circled7 white circleg7 white circleb6 white circled6 white circlef6 white circlec5 white circled5 white circlee5 white circlea4 white circleb4 white circlec4 white circled4 white queene4 white circlef4 white circleg4 white circleh4 white circlec3 white circled3 white circlee3 white circleb2 white circled2 white circlef2 white circlea1 white circled1 white circleg1 white circle
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Moves of a knight
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c7 white circlee7 white circleb6 white circlef6 white circled5 white knightb4 white circlef4 white circlec3 white circlee3 white circle
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Moves of a pawn
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b7 white crossc7 white circled7 white crossg7 black pawnc6 white pawnf6 black crossg6 black circleh6 black crossg5 black circleb4 white circlea3 white crossb3 white circlec3 white crossf3 black pawnb2 white pawne2 black crossf2 black circleg2 black cross
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The king moves one square in any direction. There is also a special move called castling which moves the king and a rook. The king is the most valuable piece—it is illegal to play any move that puts one's king under attack by an opponent piece. A move that attacks the king must be parried immediately; if this cannot be done, the game is lost. (See § Check and checkmate.)
A rook can move any number of squares along a rank or file. A rook is involved in the king's castling move.
A bishop can move any number of squares diagonally.
A queen combines the power of a rook and bishop and can move any number of squares along a rank, file, or diagonal.
A knight moves to any of the closest squares that are not on the same rank, file, or diagonal. (Thus the move forms an "L"-shape: two squares vertically and one square horizontally, or two squares horizontally and one square vertically.) The knight is the only piece that can leap over other pieces.
A pawn can move forward to the unoccupied square immediately in front of it on the same file, or on its first move it can optionally advance two squares along the same file, provided both squares are unoccupied (diagram dots). A pawn can capture an opponent's piece on a square diagonally in front of it by moving to that square (diagram crosses). It cannot capture a piece while advancing along the same file, nor can it move to either square diagonally in front without capturing. Pawns have two special moves: the en passant capture and promotion.
Check and checkmate
Main articles: Check and Checkmate
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c6 black kingc2 white rooke1 white king
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The black king is in check by the rook.
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White is in checkmate, being unable to escape attack by the bishop on f3.
When a king is under immediate attack, it is in check. A move in response to a check is legal only if it results in a position in which the king is no longer in check. There are three ways to counter a check:
Capture the checking piece.
Interpose a piece between the checking piece and the king (possible only if the attacking piece is a queen, rook, or bishop and there is a square between it and the king).
Move the king to a square where it is not under attack.
The object of the game is to checkmate the opponent; this occurs when the opponent's king is in check, and there is no legal way to get it out of check. In casual games, it is common to announce "check" when putting the opponent's king in check, but this is not required by the rules of chess and is usually not done in tournaments.[5]
Castling
Main article: Castling
Examples of castling (view animation)
Kings can castle once per game. Castling consists of moving the king two squares toward either rook of the same color, and then placing the rook on the square that the king crossed.
Castling is possible only if the following conditions are met:[2]
Neither the king nor the rook has previously moved during the game.
There are no pieces between the king and the rook.
The king is not in check and does not pass through or finish on a square controlled by an enemy piece.
Castling is still permitted if the rook is under attack, or if the rook crosses an attacked square.
Special pawn moves
Main articles: En passant and Promotion
Examples of special pawn moves: (left) promotion; (right) en passant
Pawns have two special moves:
En passant: when a pawn makes a two-square advance to the same rank as an opponent's pawn on an adjacent file, that pawn can capture it en passant ("in passing"), moving to one square behind the captured pawn. A pawn can only be captured en passant on the turn after it makes a two-square advance. In the animated diagram, the black pawn advances two squares from g7 to g5, and the white pawn on f5 takes it en passant, landing on g6.
Promotion: when a pawn advances to its last rank, it is promoted and replaced with the player's choice of a queen, rook, bishop, or knight. Usually, pawns are promoted to queens; choosing another piece is called underpromotion. In the animated diagram, the c7-pawn is advanced to c8 and promoted to a queen. If the required piece is not available (e.g. a second queen), an inverted rook is sometimes used as a substitute, but this is not recognized in FIDE-sanctioned games.
End of the game
Win
A game can be won in the following ways:
Checkmate: The opposing king is in check and the opponent has no legal move. (See § Check and checkmate.)
Resignation: A player may resign, conceding the game to the opponent.[6] If, however, the opponent has no way of checkmating the resigned player, this is a draw under FIDE Laws.[2] Most tournament players consider it good etiquette to resign in a hopeless position.[7][8]
Win on time: In games with a time control, a player wins if the opponent runs out of time, even if the opponent has a superior position, as long as the player has a theoretical possibility to checkmate the opponent were the game to continue.
Forfeit: A player who cheats, violates the rules, or violates the rules of conduct specified for the particular tournament can be forfeited. Occasionally, both players are forfeited.[2]
Draw
There are several ways a game can end in a draw:
Stalemate: If the player to move has no legal move, but is not in check, the position is a stalemate, and the game is drawn.
Dead position: If neither player is able to checkmate the other by any legal sequence of moves, the game is drawn. For example, if only the kings are on the board, all other pieces having been captured, checkmate is impossible and the game is drawn by this rule. On the other hand, if each player still has a knight, there is a theoretical albeit highly unlikely possibility of checkmate, so this rule does not apply. The dead position rule supersedes an older rule that referred to "insufficient material", thereby extending it to include other positions in which checkmate is impossible, such as blocked pawn endings in which the pawns cannot be attacked.
Draw by agreement: In tournament chess, draws are most commonly reached by mutual agreement between the players. The correct procedure is to make a move, to verbally offer the draw, and then to start the opponent's clock. If a draw is offered before making a move, the opponent has the right to ask the player to make a move before making their decision on whether or not to accept the draw offer. Traditionally, players were allowed to agree to a draw at any point in the game, occasionally even without having played a single move. Since the 2000s, efforts have been made to discourage early draws, for example by forbidding draw offers before a certain number of moves have been completed or even forbidding draw offers altogether.
Threefold repetition: This most commonly occurs when neither side is able to avoid repeating moves without incurring a disadvantage. The three occurrences of the position need not occur on consecutive moves for a claim to be valid. The addition of the fivefold repetition rule in 2014 requires the arbiter to intervene immediately and declare the game a draw after five occurrences of the same position, consecutive or otherwise, without requiring a claim by either player. FIDE rules make no mention of perpetual check; this is merely a specific type of draw by threefold repetition.
Fifty-move rule: If during the previous 50 moves no pawn has been moved and no capture has been made, either player can claim a draw. The addition of the seventy-five-move rule in 2014 requires the arbiter to intervene and immediately declare the game drawn after 75 moves without a pawn move or capture, without requiring a claim by either player. There are several known endgames in which it is possible to force a mate but it requires more than 50 moves before a pawn move or capture is made; examples include some endgames with two knights against a pawn and some pawnless endgames such as queen against two bishops. Historically, FIDE has sometimes revised the fifty-move rule to make exceptions for these endgames, but these exceptions have since been repealed. Some correspondence chess organizations do not enforce the fifty-move rule.[note 1]
Draw on time: In games with a time control, the game is drawn if a player is out of time but no sequence of legal moves would allow the opponent to checkmate the player.[2]
Draw by resignation: Under FIDE Laws, a game is drawn if a player resigns but no sequence of legal moves would allow the opponent to checkmate that player.[2]
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Black (to move) is not in check and has no legal move. The result is stalemate.
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A dead position; White's king and bishop are insufficient to deliver checkmate.
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Also a dead position; neither king can capture the other's pawns in order to promote a pawn and give checkmate.
Time control
Typical digital and analog chess clocks
In competition, chess games are played with a time control. Time controls are generally divided into categories based on the amount of time given to each player, which range from classical time controls, which allot about 2 hours or more to each player and which can take upwards of seven hours (even longer if adjournments are permitted), to bullet chess, in which players receive less than three minutes each. Between these are rapid chess (ten to sixty minutes per player), popular in amateur tournaments, and blitz chess (three to ten minutes), popular online. Non-classical chess is sometimes referred to as fast chess.
Time is controlled using a chess clock with two displays, one for each player's remaining time. Analog chess clocks have been largely replaced by digital clocks, which allow for time controls with increments.
There are some aspects unique to online chess. A premove allows a player to submit a move on the opponent's turn, which gets played automatically if possible using little to no time. Premoves, alongside the relative ease of digital inputs, make faster time controls feasible online.
Time controls are also enforced in correspondence chess competitions. A typical time control is 50 days for every 10 moves. Time is usually allotted per move in online correspondence chess.
Notation
Main article: Algebraic notation
Historically, many different notation systems have been used to record chess moves; the standard system today is short-form algebraic notation.[10] In this system, files are labeled a through h and ranks are labeled 1 through 8. Squares are identified by the file and rank they occur on; g3 is the square on the g file and the third rank. In English, the piece notations are: K (king), Q (queen), R (rook), B (bishop), and N (knight; N is used to avoid confusion with king). Different initials are used in other languages. Moves are recorded as follows:
notation of piece moved – destination square
Square names in algebraic chess notation
For example, Qg5 means "queen moves to g5". No letter initial is used for pawns, so e4 means "pawn moves to e4". When multiple moves could be rendered the same way, the file or rank from which the piece moved is added to resolve ambiguity (e.g. Ngf3 means "knight from the g-file moves to the square f3"; R1e2 means "rook on the first rank moves to e2"). If a move may be disambiguated by rank or file, it is done by file, and in the rare case that both are needed, squares are listed normally (e.g. Qh4xe1).
If the move is a capture, "x" is usually inserted before the destination square, thus Bxf3 means "bishop captures on f3". When a pawn makes a capture, the file from which the pawn departed is often listed even when no disambiguation is necessary; for example, exd5.
If a pawn moves to its last rank, achieving promotion, the piece chosen is indicated after the move (for example, e1=Q or e1Q). Castling is indicated by the special notations 0-0 for kingside castling and 0-0-0 for queenside castling. A move that places the opponent's king in check usually has the notation "+" suffixed. Checkmate can be indicated by suffixing "#". At the end of the game, "1–0" means White won, "0–1" means Black won, and "½–½" indicates a draw.[2] Chess moves can be annotated with punctuation marks and other symbols. For example: "!" indicates a good move; "!!" an excellent move; "?" a mistake; "??" a blunder; "!?" an interesting move that may not be best; or "?!" a dubious move not easily refuted.[11]
"Scholar's mate"
Moves are written as white/black pairs, preceded by the move number and a period. Individual white moves are also recorded this way, while black moves are rendered with an ellipsis after the move number. For example, one variation of a simple trap known as the Scholar's mate (see animated diagram) can be recorded:
1. e4 e5 2. Qh5?! Nc6 3. Bc4 Nf6?? 4. Qxf7#
The move 3... Nf6?? is recorded as a blunder, as it allows 4. Qxf7# checkmate.
Games or sequences may be recorded in Portable Game Notation (PGN), a text-based file format with support for annotative symbols, commentary, and background information, such as player names. It is based on short form English algebraic notation incorporating markup language. PGN transcripts, stored digitally as PGN (.pgn) files can be processed by most chess software and are easily readable by humans.
Variants of algebraic notation include long algebraic, in which both the departure and destination square are indicated; abbreviated algebraic, in which capture signs, check signs, and ranks of pawn captures may be omitted; and figurine algebraic notation, used in chess books and magazines, which uses graphic symbols instead of initials to indicate pieces for readability regardless of language.
Until about 1980, the majority of English language chess publications used descriptive notation, in which files are identified by the initial letter of the piece that occupies the first rank at the beginning of the game. In descriptive notation, the common opening move 1.e4 is rendered as "1.P-K4" ("pawn to king four"). Another system is ICCF numeric notation, recognized by the International Correspondence Chess Federation though its use is in decline.
In tournament games, players are normally required to keep a score (written record of the game). This is a requirement in all FIDE-sanctioned games played at classical time controls.[2] For this purpose, only algebraic notation is recognized by FIDE, though variants such as long algebraic are acceptable; game scores recorded in a different notation system may not be used as evidence in the event of a dispute.
Gameplay
Theory
Main articles: Chess theory, Chess libraries, List of chess books, and List of chess periodicals
Chess has an extensive literature. In 1913, the chess historian H.J.R. Murray estimated the total number of books, magazines, and chess columns in newspapers to be about 5,000.[12] B.H. Wood estimated the number, as of 1949, to be about 20,000.[13] David Hooper and Kenneth Whyld write that, "Since then there has been a steady increase year by year of the number of new chess publications. No one knows how many have been printed."[13] Significant public chess libraries include the John G. White Chess and Checkers Collection at Cleveland Public Library, with over 32,000 chess books and over 6,000 bound volumes of chess periodicals;[14] and the Chess & Draughts collection at the National Library of the Netherlands, with about 30,000 books.[15]
Strategy
Main article: Chess strategy
Example of underlying pawn structure
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a8 black rookc8 black bishope8 black rookg8 black kinga7 black pawnb7 black pawnd7 black knightf7 black pawng7 black bishoph7 black pawnc6 black pawnd6 white rookf6 black knightg6 black pawne5 black pawnc4 white pawne4 white pawnc3 white knighte3 white bishopf3 white knighth3 white pawna2 white pawnb2 white pawnf2 white pawng2 white pawnc1 white kingf1 white bishoph1 white rook
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Position after 12...Re8 ...
Tarrasch vs. Euwe, Bad Pistyan (1922)[16]
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... and its pawn structure, known as the Rauzer formation
Chess strategy is concerned with the evaluation of chess positions and with setting up goals and long-term plans for future play. During the evaluation, players must take into account numerous factors such as the value of the pieces on the board, control of the center and centralization, the pawn structure, king safety, and the control of key squares or groups of squares (for example, diagonals, open files, and dark or light squares).
The most basic step in evaluating a position is to count the total value of pieces of both sides.[17] The point values used for this purpose are based on experience; usually, pawns are considered worth one point, knights and bishops about three points each, rooks about five points (the value difference between a rook and a bishop or knight being known as the exchange), and queens about nine points. The king is more valuable than all of the other pieces combined, since its checkmate loses the game, but is still capable as a fighting piece; in the endgame, the king is generally more powerful than a bishop or knight but less powerful than a rook.[18] These basic values are then modified by other factors like position of the piece (e.g. advanced pawns are usually more valuable than those on their initial squares), coordination between pieces (e.g. a pair of bishops usually coordinate better than a bishop and a knight), or the type of position (e.g. knights are generally better in closed positions with many pawns while bishops are more powerful in open positions).[19]
Another important factor in the evaluation of chess positions is pawn structure (sometimes known as the pawn skeleton): the configuration of pawns on the chessboard.[20] Since pawns are the least mobile of the pieces, pawn structure is relatively static and largely determines the strategic nature of the position. Weaknesses in pawn structure include isolated, doubled, or backward pawns and holes; once created, they are often permanent. Care must therefore be taken to avoid these weaknesses unless they are compensated by another valuable asset (for example, by the possibility of developing an attack).[21]
Tactics
Main article: Chess tactic
In chess, tactics generally refer to short-term maneuvers – so short-term that they can be calculated in advance by a human player. The possible depth of calculation depends on the player's ability. In quiet positions with many possibilities on both sides, a deep calculation is more difficult and may not be practical, while in positions with a limited number of forced variations, strong players can calculate long sequences of moves.
Theoreticians describe many elementary tactical methods and typical maneuvers, for example: pins, forks, skewers, batteries, discovered attacks (especially discovered checks), zwischenzugs, deflections, decoys, sacrifices, underminings, overloadings, and interferences.[22] Simple one-move or two-move tactical actions – threats, exchanges of material, and double attacks – can be combined into longer sequences of tactical maneuvers that are often forced from the point of view of one or both players. A forced variation that involves a sacrifice and usually results in a tangible gain is called a combination.[23] Brilliant combinations – such as those in the Immortal Game – are considered beautiful and are admired by chess lovers.
A common type of chess exercise, aimed at developing players' tactical skills, is a position where a combination is available and the challenge is to find it. Such positions are usually taken from actual games or from analysis of actual games. Solutions usually result in checkmate, decisive advantage, or successful defense. Tactical exercises are commonly found in instructional books, chess magazines, newspaper chess columns, and internet chess sites.[24]
Phases
Chess theory divides chess games into three phases with different sets of strategies: the opening, the middlegame, and lastly the endgame. There is no universally accepted way to delineate the three phases of the game; the middlegame is typically considered to have begun after 10–20 moves, and the endgame when only a few pieces remain.
Opening
Main article: Chess opening
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a8 black rookb8 black knightc8 black bishopd8 black queene8 black kingf8 black bishoph8 black rookb7 black pawne7 black pawnf7 black pawng7 black pawnh7 black pawna6 black pawnd6 black pawnf6 black knightd4 white knighte4 white pawnc3 white knighta2 white pawnb2 white pawnc2 white pawnf2 white pawng2 white pawnh2 white pawna1 white rookc1 white bishopd1 white queene1 white kingf1 white bishoph1 white rook
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The Najdorf Variation (5...a6), a popular line of the Sicilian Defense (1...c5), itself a response to the King's Pawn Game (1.e4)
Competitive players typically learn, memorize, and play well-documented sequences of opening moves. The most common starting moves for White are 1.e4 and 1.d4, which usually lead to substantially different types of positions, and Black has multiple viable responses to both.
Sequences of opening moves are referred to as openings and are catalogued in reference works, such as the Encyclopaedia of Chess Openings. There are thousands of openings, though only a small fraction of them are commonly played; variations of openings may also be given names. Openings vary widely in character from quiet positional play (for example, the Réti Opening) to sharp aggressive play (like the Latvian Gambit). In some opening lines, the exact sequence considered best for both sides has been worked out to more than 30 moves.[25]
The fundamental strategic aims of most openings are similar:[26]
Development: moving pieces (particularly bishops and knights) forward to squares on which they are useful (defending, attacking, and controlling important squares) or have the potential to take part in future plans and ideas.
Control of the center: control of the central squares allows pieces to be moved to any part of the board relatively easily, and can inhibit the mobility of the opponent's pieces.
King safety: typically secured by castling; incorrectly timed castling can be wasteful or even harmful, however.
Pawn structure: players strive to avoid the creation of pawn weaknesses such as isolated, doubled, or backward pawns – and to force such weaknesses in the opponent's position.
Most players and theoreticians consider that White, by virtue of the initiative granted from moving first, begins the game with a small advantage.[27] Black usually strives to neutralize White's advantage and achieve equality, or to develop dynamic counterplay in an unbalanced position.
Middlegame
Main article: Chess middlegame
The middlegame is the part of the game that starts after the opening. Because the opening theory has ended, players have to form plans based on the features of the position, and at the same time take into account the tactical possibilities of the position.[28] The middlegame is the phase in which most combinations occur. Combinations are a series of tactical moves executed to achieve some gain. Middlegame combinations are often connected with an attack against the opponent's king. Some typical patterns have their own names; for example, the Boden's Mate or the Lasker–Bauer combination.[29]
Specific plans or strategic themes will often arise from particular groups of openings that result in a specific type of pawn structure. An example is the minority attack, which is the attack of queenside pawns against an opponent who has more pawns on the queenside. The study of openings is therefore connected to the preparation of plans that are typical of the resulting middlegames.[30]
Another important strategic question in the middlegame is whether and how to reduce material and transition into an endgame (i.e. simplify). Minor material advantages can generally be transformed into victory only in an endgame, and therefore the stronger side must choose an appropriate way to achieve an ending. Not every reduction of material is good for this purpose; for example, if one side keeps a light-squared bishop and the opponent has a dark-squared one, the transformation into a bishops and pawns ending is usually advantageous for the weaker side only, because an endgame with bishops on opposite colors is likely to be a draw, even with an advantage of a pawn, or sometimes even with a two-pawn advantage.[31]
Endgame
Main article: Chess endgame
Example of zugzwang
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The side to move is disadvantaged.
The endgame (also end game or ending) is the stage of the game when there are few pieces left on the board. There are three main strategic differences between earlier stages of the game and the endgame:[32]
Pawns become more important. Endgames often revolve around endeavors to promote a pawn by advancing it to the furthest rank.
The king, which requires safeguarding from attack during the middlegame, emerges as a strong piece in the endgame. It is often used to protect its own pawns, attack enemy pawns, and hinder moves of the opponent's king.
Zugzwang, a situation in which the player who is to move is forced to incur a disadvantage, is often a factor in endgames but rarely in other stages of the game. In the example diagram, either side having the move is in zugzwang: Black to move must play 1...Kb7 allowing White to promote the pawn after 2.Kd7; White to move must permit a draw, either by 1.Kc6 stalemate or by losing the pawn after any other legal move.
Endgames can be classified according to the type of pieces remaining on the board. Basic checkmates are positions in which one side has only a king and the other side has one or two pieces and can checkmate the opposing king, with the pieces working together with their king. For example, king and pawn endgames involve only kings and pawns on one or both sides, and the task of the stronger side is to promote one of the pawns. Other more complicated endings are classified according to pieces on the board other than kings, such as "rook and pawn versus rook" endgames.
Problems and studies
Richard Réti
Ostrauer Morgenzeitung, 1921
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This endgame study is solved by advancing the white king diagonally, simultaneously stopping the black pawn and supporting the white pawn on its way to queen.[33]
Chess problems (also called chess compositions) are composed positions, usually created for artistic effect rather than practical application. The creator is known as a chess composer.[34]
There are many types of chess problems, the most common being directmates, in which White is required to move and checkmate Black within a specified number of moves, usually two or three, against any defense.
These are commonly referred to as "two-movers", "three-movers", or "more-movers". "Many-movers" (also known as "long-range problems") of over 100 moves have been composed, the current record standing at over 200; these usually require repetitions of the same manoeuvre in order to produce a repeated zugzwang and force detrimental pawn advances.[35][36]
Directmates usually consist of positions unlikely to occur in an actual game, and are intended to illustrate a particular theme, usually requiring a surprising or counterintuitive key move. Themes associated with chess problems occasionally appear in actual games, when they are referred to as "problem-like" moves.[37]
Other common types of problems include:
Helpmates, in which Black moves first and cooperates with White to get Black's king checkmated
Selfmates, in which White moves first and forces Black to checkmate White
Retrograde analysis problems, in which the solver is required to work out what has previously occurred in the game, for example to prove that castling is illegal in the current position
The above type of problems are usually considered orthodox, in the sense that the standard rules of chess are observed.
Fairy chess problems, also called heterodox problems, involve altered rules, such as the use of unconventional pieces or boards, or stipulations that contradict the standard rules of chess such as reflexmates or seriesmovers.
Studies are usually considered distinct from problems, although there is some overlap. In a study, the stipulation is that White to play must win or draw, without specifying any particular number of moves. The majority of studies are endgame positions, with varying degrees of realism or practical application.[38]
Tournaments for composition and solving of chess problems and studies are organized by the World Federation for Chess Composition (WFCC), which works cooperatively with but independent of FIDE. The WFCC awards titles for composing and solving chess problems.[39]
Chess in public spaces
Chess is often played in public spaces such as parks and town squares. Although the nature of these games is often casual, the chess hustling scene has seen growth in urban areas such as New York City.[40]
A child playing chess in Washington Square Park, New York City, US
A child playing chess in Washington Square Park, New York City, US
Public chess tables in the Jardin du Luxembourg, Paris, France
Public chess tables in the Jardin du Luxembourg, Paris, France
Men playing chess, Kutaisi, Georgia, 2014
Men playing chess, Kutaisi, Georgia, 2014
A girl playing chess in Mexico City, Mexico
A girl playing chess in Mexico City, Mexico
Chess game in Kilifi, Kenya
Chess game in Kilifi, Kenya
Giant chess in Cathedral Square, Christchurch, New Zealand, 2005
Giant chess in Cathedral Square, Christchurch, New Zealand, 2005
Boys playing chess on a street in Santiago de Cuba, Cuba
Boys playing chess on a street in Santiago de Cuba, Cuba
Chess players in the Széchenyi baths of Budapest, Hungary
Chess players in the Széchenyi baths of Budapest, Hungary
A girl playing chess in Salatiga, Indonesia
A girl playing chess in Salatiga, Indonesia
Two men play chess at the Ariman cafe in Lund in 2007.
Two men play chess at the Ariman cafe in Lund in 2007.
Organized competition
Tournaments and matches
Tata Steel Chess Tournament 2019, Wijk aan Zee (the Netherlands)
Contemporary chess is an organized sport with structured international and national leagues, tournaments, and congresses. Thousands of chess tournaments, matches, and festivals are held around the world every year catering to players of all levels.
Tournaments with a small number of players may use the round-robin format, in which every player plays one game against every other player. For a large number of players, the Swiss system may be used, in which each player is paired against an opponent who has the same (or as similar as possible) score in each round. In either case, a player's score is usually calculated as 1 point for each game won and one-half point for each game drawn. Variations such as "football scoring" (3 points for a win, 1 point for a draw) may be used by tournament organizers, but ratings are always calculated on the basis of standard scoring. A player's score may be reported as total score out of games played (e.g. 5½/8), points for versus points against (e.g. 5½–2½), or by number of wins, losses and draws (e.g. +4−1=3).
The term "match" refers not to an individual game, but to either a se
This article is about the Western board game. For other chess games or other uses, see Chess (disambiguation).
Chess
Part of a Staunton chess set
Left to right: white king, black rook, black queen, white pawn, black knight, white bishop
Years active
c. 1475 to present[1] (predecessors c. 900 years earlier)
Genres
Board game
Abstract strategy game
Mind sport
Players
2
Chance
None
Skills
Strategy, tactics
Synonyms
International chess
Western chess
Chess is a board game for two players. It is an abstract strategy game that involves no hidden information and no elements of chance. It is played on a square board consisting of 64 squares arranged in an 8×8 grid. The players, referred to as "White" and "Black", each control sixteen pieces: one king, one queen, two rooks, two bishops, two knights, and eight pawns, with each type of piece having a different pattern of movement. An enemy piece may be captured (removed from the board) by moving one's own piece onto the square it occupies. The object of the game is to "checkmate" (threaten with inescapable capture) the enemy king. There are also several ways a game can end in a draw.
The recorded history of chess goes back to at least the emergence of chaturanga—also thought to be an ancestor to similar games like Janggi, xiangqi and shogi—in seventh-century India. After its introduction in Persia, it spread to the Arab world and then to Europe. The modern rules of chess emerged in Europe at the end of the 15th century, with standardization and universal acceptance by the end of the 19th century. Today, chess is one of the world's most popular games, with millions of players worldwide.
Organized chess arose in the 19th century. Chess competition today is governed internationally by FIDE (Fédération Internationale des Échecs), the International Chess Federation. The first universally recognized World Chess Champion, Wilhelm Steinitz, claimed his title in 1886; Gukesh Dommaraju is the current World Champion, having won the title in 2024.
A huge body of chess theory has developed since the game's inception. Aspects of art are found in chess composition, and chess in its turn influenced Western culture and the arts, and has connections with other fields such as mathematics, computer science, and psychology. One of the goals of early computer scientists was to create a chess-playing machine. In 1997, Deep Blue became the first computer to beat a reigning World Champion in a match when it defeated Garry Kasparov. Today's chess engines are significantly stronger than the best human players and have deeply influenced the development of chess theory; however, chess is not a solved game.
This article uses algebraic notation to describe chess moves.
Rules
Main article: Rules of chess
The rules of chess are published by FIDE (Fédération Internationale des Échecs; "International Chess Federation"), chess's world governing body, in its Handbook.[2] Rules published by national governing bodies, or by unaffiliated chess organizations, commercial publishers, etc., may differ in some details. FIDE's rules were most recently revised in 2023.
Setup
Setup at the start of a chess game
Chess sets come in a wide variety of styles. The Staunton pattern is the most common, and is usually required for competition.[3] Chess sets come with pieces in two colors, referred to as white and black, regardless of their actual color; the players controlling the color sets are referred to as White and Black, respectively. Each set comes with at least the following 16 pieces in both colors: one king, one queen, two rooks, two bishops, two knights, and eight pawns.[2]
The game is played on a square board of eight rows (called ranks) and eight columns (called files). Although it does not affect gameplay, by convention the 64 squares alternate in color and are referred to as light and dark squares.[2]
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Initial position: first row: rook, knight, bishop, queen, king, bishop, knight, rook; second row: pawns
To start the game, White's pieces are placed on the first rank in the following order, from left to right: rook, knight, bishop, queen, king, bishop, knight, rook. Pawns are placed on each square of the second rank. Black's position mirrors White's, with equivalent pieces on every file.[2] The board is oriented so that the right-hand corner nearest each player is a light square; as a result the white queen always starts on a light square, while the black queen starts on a dark square. This may be remembered by the phrases "white on the right" and "queen on her color".[4]
In competition, the piece colors are allocated to players by the organizers. In informal games, colors may be decided either by mutual agreement, or randomly, for example by a coin toss, or by one player concealing a white pawn in one hand and a black pawn in the other and having the opponent choose.[citation needed]
Movement
White moves first, after which players alternate turns. One piece is moved per turn (except when castling, during which two pieces are moved). In the diagrams, dots mark the squares to which each type of piece can move if unoccupied by friendly pieces and there are no intervening piece(s) of either color (except the knight, which leaps over any intervening pieces). With the sole exception of en passant, a piece captures an enemy piece by moving to the square it occupies, removing it from play and taking its place. The pawn is the only piece that does not capture the way it moves, and it is the only piece that moves and captures in only one direction (forwards from the player's perspective). A piece is said to control empty squares on which it could capture, attack squares with enemy pieces it could capture, and defend squares with pieces of the same color on which it could recapture. Moving is compulsory; a player may not skip a turn, even when having to move is detrimental.
Moves of the king
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Moves of a rook
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Moves of a bishop
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Moves of a queen
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Moves of a knight
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Moves of a pawn
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The king moves one square in any direction. There is also a special move called castling which moves the king and a rook. The king is the most valuable piece—it is illegal to play any move that puts one's king under attack by an opponent piece. A move that attacks the king must be parried immediately; if this cannot be done, the game is lost. (See § Check and checkmate.)
A rook can move any number of squares along a rank or file. A rook is involved in the king's castling move.
A bishop can move any number of squares diagonally.
A queen combines the power of a rook and bishop and can move any number of squares along a rank, file, or diagonal.
A knight moves to any of the closest squares that are not on the same rank, file, or diagonal. (Thus the move forms an "L"-shape: two squares vertically and one square horizontally, or two squares horizontally and one square vertically.) The knight is the only piece that can leap over other pieces.
A pawn can move forward to the unoccupied square immediately in front of it on the same file, or on its first move it can optionally advance two squares along the same file, provided both squares are unoccupied (diagram dots). A pawn can capture an opponent's piece on a square diagonally in front of it by moving to that square (diagram crosses). It cannot capture a piece while advancing along the same file, nor can it move to either square diagonally in front without capturing. Pawns have two special moves: the en passant capture and promotion.
Check and checkmate
Main articles: Check and Checkmate
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The black king is in check by the rook.
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White is in checkmate, being unable to escape attack by the bishop on f3.
When a king is under immediate attack, it is in check. A move in response to a check is legal only if it results in a position in which the king is no longer in check. There are three ways to counter a check:
Capture the checking piece.
Interpose a piece between the checking piece and the king (possible only if the attacking piece is a queen, rook, or bishop and there is a square between it and the king).
Move the king to a square where it is not under attack.
The object of the game is to checkmate the opponent; this occurs when the opponent's king is in check, and there is no legal way to get it out of check. In casual games, it is common to announce "check" when putting the opponent's king in check, but this is not required by the rules of chess and is usually not done in tournaments.[5]
Castling
Main article: Castling
Examples of castling (view animation)
Kings can castle once per game. Castling consists of moving the king two squares toward either rook of the same color, and then placing the rook on the square that the king crossed.
Castling is possible only if the following conditions are met:[2]
Neither the king nor the rook has previously moved during the game.
There are no pieces between the king and the rook.
The king is not in check and does not pass through or finish on a square controlled by an enemy piece.
Castling is still permitted if the rook is under attack, or if the rook crosses an attacked square.
Special pawn moves
Main articles: En passant and Promotion
Examples of special pawn moves: (left) promotion; (right) en passant
Pawns have two special moves:
En passant: when a pawn makes a two-square advance to the same rank as an opponent's pawn on an adjacent file, that pawn can capture it en passant ("in passing"), moving to one square behind the captured pawn. A pawn can only be captured en passant on the turn after it makes a two-square advance. In the animated diagram, the black pawn advances two squares from g7 to g5, and the white pawn on f5 takes it en passant, landing on g6.
Promotion: when a pawn advances to its last rank, it is promoted and replaced with the player's choice of a queen, rook, bishop, or knight. Usually, pawns are promoted to queens; choosing another piece is called underpromotion. In the animated diagram, the c7-pawn is advanced to c8 and promoted to a queen. If the required piece is not available (e.g. a second queen), an inverted rook is sometimes used as a substitute, but this is not recognized in FIDE-sanctioned games.
End of the game
Win
A game can be won in the following ways:
Checkmate: The opposing king is in check and the opponent has no legal move. (See § Check and checkmate.)
Resignation: A player may resign, conceding the game to the opponent.[6] If, however, the opponent has no way of checkmating the resigned player, this is a draw under FIDE Laws.[2] Most tournament players consider it good etiquette to resign in a hopeless position.[7][8]
Win on time: In games with a time control, a player wins if the opponent runs out of time, even if the opponent has a superior position, as long as the player has a theoretical possibility to checkmate the opponent were the game to continue.
Forfeit: A player who cheats, violates the rules, or violates the rules of conduct specified for the particular tournament can be forfeited. Occasionally, both players are forfeited.[2]
Draw
There are several ways a game can end in a draw:
Stalemate: If the player to move has no legal move, but is not in check, the position is a stalemate, and the game is drawn.
Dead position: If neither player is able to checkmate the other by any legal sequence of moves, the game is drawn. For example, if only the kings are on the board, all other pieces having been captured, checkmate is impossible and the game is drawn by this rule. On the other hand, if each player still has a knight, there is a theoretical albeit highly unlikely possibility of checkmate, so this rule does not apply. The dead position rule supersedes an older rule that referred to "insufficient material", thereby extending it to include other positions in which checkmate is impossible, such as blocked pawn endings in which the pawns cannot be attacked.
Draw by agreement: In tournament chess, draws are most commonly reached by mutual agreement between the players. The correct procedure is to make a move, to verbally offer the draw, and then to start the opponent's clock. If a draw is offered before making a move, the opponent has the right to ask the player to make a move before making their decision on whether or not to accept the draw offer. Traditionally, players were allowed to agree to a draw at any point in the game, occasionally even without having played a single move. Since the 2000s, efforts have been made to discourage early draws, for example by forbidding draw offers before a certain number of moves have been completed or even forbidding draw offers altogether.
Threefold repetition: This most commonly occurs when neither side is able to avoid repeating moves without incurring a disadvantage. The three occurrences of the position need not occur on consecutive moves for a claim to be valid. The addition of the fivefold repetition rule in 2014 requires the arbiter to intervene immediately and declare the game a draw after five occurrences of the same position, consecutive or otherwise, without requiring a claim by either player. FIDE rules make no mention of perpetual check; this is merely a specific type of draw by threefold repetition.
Fifty-move rule: If during the previous 50 moves no pawn has been moved and no capture has been made, either player can claim a draw. The addition of the seventy-five-move rule in 2014 requires the arbiter to intervene and immediately declare the game drawn after 75 moves without a pawn move or capture, without requiring a claim by either player. There are several known endgames in which it is possible to force a mate but it requires more than 50 moves before a pawn move or capture is made; examples include some endgames with two knights against a pawn and some pawnless endgames such as queen against two bishops. Historically, FIDE has sometimes revised the fifty-move rule to make exceptions for these endgames, but these exceptions have since been repealed. Some correspondence chess organizations do not enforce the fifty-move rule.[note 1]
Draw on time: In games with a time control, the game is drawn if a player is out of time but no sequence of legal moves would allow the opponent to checkmate the player.[2]
Draw by resignation: Under FIDE Laws, a game is drawn if a player resigns but no sequence of legal moves would allow the opponent to checkmate that player.[2]
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Black (to move) is not in check and has no legal move. The result is stalemate.
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A dead position; White's king and bishop are insufficient to deliver checkmate.
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Also a dead position; neither king can capture the other's pawns in order to promote a pawn and give checkmate.
Time control
Typical digital and analog chess clocks
In competition, chess games are played with a time control. Time controls are generally divided into categories based on the amount of time given to each player, which range from classical time controls, which allot about 2 hours or more to each player and which can take upwards of seven hours (even longer if adjournments are permitted), to bullet chess, in which players receive less than three minutes each. Between these are rapid chess (ten to sixty minutes per player), popular in amateur tournaments, and blitz chess (three to ten minutes), popular online. Non-classical chess is sometimes referred to as fast chess.
Time is controlled using a chess clock with two displays, one for each player's remaining time. Analog chess clocks have been largely replaced by digital clocks, which allow for time controls with increments.
There are some aspects unique to online chess. A premove allows a player to submit a move on the opponent's turn, which gets played automatically if possible using little to no time. Premoves, alongside the relative ease of digital inputs, make faster time controls feasible online.
Time controls are also enforced in correspondence chess competitions. A typical time control is 50 days for every 10 moves. Time is usually allotted per move in online correspondence chess.
Notation
Main article: Algebraic notation
Historically, many different notation systems have been used to record chess moves; the standard system today is short-form algebraic notation.[10] In this system, files are labeled a through h and ranks are labeled 1 through 8. Squares are identified by the file and rank they occur on; g3 is the square on the g file and the third rank. In English, the piece notations are: K (king), Q (queen), R (rook), B (bishop), and N (knight; N is used to avoid confusion with king). Different initials are used in other languages. Moves are recorded as follows:
notation of piece moved – destination square
Square names in algebraic chess notation
For example, Qg5 means "queen moves to g5". No letter initial is used for pawns, so e4 means "pawn moves to e4". When multiple moves could be rendered the same way, the file or rank from which the piece moved is added to resolve ambiguity (e.g. Ngf3 means "knight from the g-file moves to the square f3"; R1e2 means "rook on the first rank moves to e2"). If a move may be disambiguated by rank or file, it is done by file, and in the rare case that both are needed, squares are listed normally (e.g. Qh4xe1).
If the move is a capture, "x" is usually inserted before the destination square, thus Bxf3 means "bishop captures on f3". When a pawn makes a capture, the file from which the pawn departed is often listed even when no disambiguation is necessary; for example, exd5.
If a pawn moves to its last rank, achieving promotion, the piece chosen is indicated after the move (for example, e1=Q or e1Q). Castling is indicated by the special notations 0-0 for kingside castling and 0-0-0 for queenside castling. A move that places the opponent's king in check usually has the notation "+" suffixed. Checkmate can be indicated by suffixing "#". At the end of the game, "1–0" means White won, "0–1" means Black won, and "½–½" indicates a draw.[2] Chess moves can be annotated with punctuation marks and other symbols. For example: "!" indicates a good move; "!!" an excellent move; "?" a mistake; "??" a blunder; "!?" an interesting move that may not be best; or "?!" a dubious move not easily refuted.[11]
"Scholar's mate"
Moves are written as white/black pairs, preceded by the move number and a period. Individual white moves are also recorded this way, while black moves are rendered with an ellipsis after the move number. For example, one variation of a simple trap known as the Scholar's mate (see animated diagram) can be recorded:
1. e4 e5 2. Qh5?! Nc6 3. Bc4 Nf6?? 4. Qxf7#
The move 3... Nf6?? is recorded as a blunder, as it allows 4. Qxf7# checkmate.
Games or sequences may be recorded in Portable Game Notation (PGN), a text-based file format with support for annotative symbols, commentary, and background information, such as player names. It is based on short form English algebraic notation incorporating markup language. PGN transcripts, stored digitally as PGN (.pgn) files can be processed by most chess software and are easily readable by humans.
Variants of algebraic notation include long algebraic, in which both the departure and destination square are indicated; abbreviated algebraic, in which capture signs, check signs, and ranks of pawn captures may be omitted; and figurine algebraic notation, used in chess books and magazines, which uses graphic symbols instead of initials to indicate pieces for readability regardless of language.
Until about 1980, the majority of English language chess publications used descriptive notation, in which files are identified by the initial letter of the piece that occupies the first rank at the beginning of the game. In descriptive notation, the common opening move 1.e4 is rendered as "1.P-K4" ("pawn to king four"). Another system is ICCF numeric notation, recognized by the International Correspondence Chess Federation though its use is in decline.
In tournament games, players are normally required to keep a score (written record of the game). This is a requirement in all FIDE-sanctioned games played at classical time controls.[2] For this purpose, only algebraic notation is recognized by FIDE, though variants such as long algebraic are acceptable; game scores recorded in a different notation system may not be used as evidence in the event of a dispute.
Gameplay
Theory
Main articles: Chess theory, Chess libraries, List of chess books, and List of chess periodicals
Chess has an extensive literature. In 1913, the chess historian H.J.R. Murray estimated the total number of books, magazines, and chess columns in newspapers to be about 5,000.[12] B.H. Wood estimated the number, as of 1949, to be about 20,000.[13] David Hooper and Kenneth Whyld write that, "Since then there has been a steady increase year by year of the number of new chess publications. No one knows how many have been printed."[13] Significant public chess libraries include the John G. White Chess and Checkers Collection at Cleveland Public Library, with over 32,000 chess books and over 6,000 bound volumes of chess periodicals;[14] and the Chess & Draughts collection at the National Library of the Netherlands, with about 30,000 books.[15]
Strategy
Main article: Chess strategy
Example of underlying pawn structure
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Position after 12...Re8 ...
Tarrasch vs. Euwe, Bad Pistyan (1922)[16]
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... and its pawn structure, known as the Rauzer formation
Chess strategy is concerned with the evaluation of chess positions and with setting up goals and long-term plans for future play. During the evaluation, players must take into account numerous factors such as the value of the pieces on the board, control of the center and centralization, the pawn structure, king safety, and the control of key squares or groups of squares (for example, diagonals, open files, and dark or light squares).
The most basic step in evaluating a position is to count the total value of pieces of both sides.[17] The point values used for this purpose are based on experience; usually, pawns are considered worth one point, knights and bishops about three points each, rooks about five points (the value difference between a rook and a bishop or knight being known as the exchange), and queens about nine points. The king is more valuable than all of the other pieces combined, since its checkmate loses the game, but is still capable as a fighting piece; in the endgame, the king is generally more powerful than a bishop or knight but less powerful than a rook.[18] These basic values are then modified by other factors like position of the piece (e.g. advanced pawns are usually more valuable than those on their initial squares), coordination between pieces (e.g. a pair of bishops usually coordinate better than a bishop and a knight), or the type of position (e.g. knights are generally better in closed positions with many pawns while bishops are more powerful in open positions).[19]
Another important factor in the evaluation of chess positions is pawn structure (sometimes known as the pawn skeleton): the configuration of pawns on the chessboard.[20] Since pawns are the least mobile of the pieces, pawn structure is relatively static and largely determines the strategic nature of the position. Weaknesses in pawn structure include isolated, doubled, or backward pawns and holes; once created, they are often permanent. Care must therefore be taken to avoid these weaknesses unless they are compensated by another valuable asset (for example, by the possibility of developing an attack).[21]
Tactics
Main article: Chess tactic
In chess, tactics generally refer to short-term maneuvers – so short-term that they can be calculated in advance by a human player. The possible depth of calculation depends on the player's ability. In quiet positions with many possibilities on both sides, a deep calculation is more difficult and may not be practical, while in positions with a limited number of forced variations, strong players can calculate long sequences of moves.
Theoreticians describe many elementary tactical methods and typical maneuvers, for example: pins, forks, skewers, batteries, discovered attacks (especially discovered checks), zwischenzugs, deflections, decoys, sacrifices, underminings, overloadings, and interferences.[22] Simple one-move or two-move tactical actions – threats, exchanges of material, and double attacks – can be combined into longer sequences of tactical maneuvers that are often forced from the point of view of one or both players. A forced variation that involves a sacrifice and usually results in a tangible gain is called a combination.[23] Brilliant combinations – such as those in the Immortal Game – are considered beautiful and are admired by chess lovers.
A common type of chess exercise, aimed at developing players' tactical skills, is a position where a combination is available and the challenge is to find it. Such positions are usually taken from actual games or from analysis of actual games. Solutions usually result in checkmate, decisive advantage, or successful defense. Tactical exercises are commonly found in instructional books, chess magazines, newspaper chess columns, and internet chess sites.[24]
Phases
Chess theory divides chess games into three phases with different sets of strategies: the opening, the middlegame, and lastly the endgame. There is no universally accepted way to delineate the three phases of the game; the middlegame is typically considered to have begun after 10–20 moves, and the endgame when only a few pieces remain.
Opening
Main article: Chess opening
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The Najdorf Variation (5...a6), a popular line of the Sicilian Defense (1...c5), itself a response to the King's Pawn Game (1.e4)
Competitive players typically learn, memorize, and play well-documented sequences of opening moves. The most common starting moves for White are 1.e4 and 1.d4, which usually lead to substantially different types of positions, and Black has multiple viable responses to both.
Sequences of opening moves are referred to as openings and are catalogued in reference works, such as the Encyclopaedia of Chess Openings. There are thousands of openings, though only a small fraction of them are commonly played; variations of openings may also be given names. Openings vary widely in character from quiet positional play (for example, the Réti Opening) to sharp aggressive play (like the Latvian Gambit). In some opening lines, the exact sequence considered best for both sides has been worked out to more than 30 moves.[25]
The fundamental strategic aims of most openings are similar:[26]
Development: moving pieces (particularly bishops and knights) forward to squares on which they are useful (defending, attacking, and controlling important squares) or have the potential to take part in future plans and ideas.
Control of the center: control of the central squares allows pieces to be moved to any part of the board relatively easily, and can inhibit the mobility of the opponent's pieces.
King safety: typically secured by castling; incorrectly timed castling can be wasteful or even harmful, however.
Pawn structure: players strive to avoid the creation of pawn weaknesses such as isolated, doubled, or backward pawns – and to force such weaknesses in the opponent's position.
Most players and theoreticians consider that White, by virtue of the initiative granted from moving first, begins the game with a small advantage.[27] Black usually strives to neutralize White's advantage and achieve equality, or to develop dynamic counterplay in an unbalanced position.
Middlegame
Main article: Chess middlegame
The middlegame is the part of the game that starts after the opening. Because the opening theory has ended, players have to form plans based on the features of the position, and at the same time take into account the tactical possibilities of the position.[28] The middlegame is the phase in which most combinations occur. Combinations are a series of tactical moves executed to achieve some gain. Middlegame combinations are often connected with an attack against the opponent's king. Some typical patterns have their own names; for example, the Boden's Mate or the Lasker–Bauer combination.[29]
Specific plans or strategic themes will often arise from particular groups of openings that result in a specific type of pawn structure. An example is the minority attack, which is the attack of queenside pawns against an opponent who has more pawns on the queenside. The study of openings is therefore connected to the preparation of plans that are typical of the resulting middlegames.[30]
Another important strategic question in the middlegame is whether and how to reduce material and transition into an endgame (i.e. simplify). Minor material advantages can generally be transformed into victory only in an endgame, and therefore the stronger side must choose an appropriate way to achieve an ending. Not every reduction of material is good for this purpose; for example, if one side keeps a light-squared bishop and the opponent has a dark-squared one, the transformation into a bishops and pawns ending is usually advantageous for the weaker side only, because an endgame with bishops on opposite colors is likely to be a draw, even with an advantage of a pawn, or sometimes even with a two-pawn advantage.[31]
Endgame
Main article: Chess endgame
Example of zugzwang
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The side to move is disadvantaged.
The endgame (also end game or ending) is the stage of the game when there are few pieces left on the board. There are three main strategic differences between earlier stages of the game and the endgame:[32]
Pawns become more important. Endgames often revolve around endeavors to promote a pawn by advancing it to the furthest rank.
The king, which requires safeguarding from attack during the middlegame, emerges as a strong piece in the endgame. It is often used to protect its own pawns, attack enemy pawns, and hinder moves of the opponent's king.
Zugzwang, a situation in which the player who is to move is forced to incur a disadvantage, is often a factor in endgames but rarely in other stages of the game. In the example diagram, either side having the move is in zugzwang: Black to move must play 1...Kb7 allowing White to promote the pawn after 2.Kd7; White to move must permit a draw, either by 1.Kc6 stalemate or by losing the pawn after any other legal move.
Endgames can be classified according to the type of pieces remaining on the board. Basic checkmates are positions in which one side has only a king and the other side has one or two pieces and can checkmate the opposing king, with the pieces working together with their king. For example, king and pawn endgames involve only kings and pawns on one or both sides, and the task of the stronger side is to promote one of the pawns. Other more complicated endings are classified according to pieces on the board other than kings, such as "rook and pawn versus rook" endgames.
Problems and studies
Richard Réti
Ostrauer Morgenzeitung, 1921
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White to move and draw
This endgame study is solved by advancing the white king diagonally, simultaneously stopping the black pawn and supporting the white pawn on its way to queen.[33]
Chess problems (also called chess compositions) are composed positions, usually created for artistic effect rather than practical application. The creator is known as a chess composer.[34]
There are many types of chess problems, the most common being directmates, in which White is required to move and checkmate Black within a specified number of moves, usually two or three, against any defense.
These are commonly referred to as "two-movers", "three-movers", or "more-movers". "Many-movers" (also known as "long-range problems") of over 100 moves have been composed, the current record standing at over 200; these usually require repetitions of the same manoeuvre in order to produce a repeated zugzwang and force detrimental pawn advances.[35][36]
Directmates usually consist of positions unlikely to occur in an actual game, and are intended to illustrate a particular theme, usually requiring a surprising or counterintuitive key move. Themes associated with chess problems occasionally appear in actual games, when they are referred to as "problem-like" moves.[37]
Other common types of problems include:
Helpmates, in which Black moves first and cooperates with White to get Black's king checkmated
Selfmates, in which White moves first and forces Black to checkmate White
Retrograde analysis problems, in which the solver is required to work out what has previously occurred in the game, for example to prove that castling is illegal in the current position
The above type of problems are usually considered orthodox, in the sense that the standard rules of chess are observed.
Fairy chess problems, also called heterodox problems, involve altered rules, such as the use of unconventional pieces or boards, or stipulations that contradict the standard rules of chess such as reflexmates or seriesmovers.
Studies are usually considered distinct from problems, although there is some overlap. In a study, the stipulation is that White to play must win or draw, without specifying any particular number of moves. The majority of studies are endgame positions, with varying degrees of realism or practical application.[38]
Tournaments for composition and solving of chess problems and studies are organized by the World Federation for Chess Composition (WFCC), which works cooperatively with but independent of FIDE. The WFCC awards titles for composing and solving chess problems.[39]
Chess in public spaces
Chess is often played in public spaces such as parks and town squares. Although the nature of these games is often casual, the chess hustling scene has seen growth in urban areas such as New York City.[40]
A child playing chess in Washington Square Park, New York City, US
Public chess tables in the Jardin du Luxembourg, Paris, France
Men playing chess, Kutaisi, Georgia, 2014
A girl playing chess in Mexico City, Mexico
Chess game in Kilifi, Kenya
Giant chess in Cathedral Square, Christchurch, New Zealand, 2005
Boys playing chess on a street in Santiago de Cuba, Cuba
Chess players in the Széchenyi baths of Budapest, Hungary
A girl playing chess in Salatiga, Indonesia
Two men play chess at the Ariman cafe in Lund in 2007.
Organized competition
Tournaments and matches
Tata Steel Chess Tournament 2019, Wijk aan Zee (the Netherlands)
Contemporary chess is an organized sport with structured international and national leagues, tournaments, and congresses. Thousands of chess tournaments, matches, and festivals are held around the world every year catering to players of all levels.
Tournaments with a small number of players may use the round-robin format, in which every player plays one game against every other player. For a large number of players, the Swiss system may be used, in which each player is paired against an opponent who has the same (or as similar as possible) score in each round. In either case, a player's score is usually calculated as 1 point for each game won and one-half point for each game drawn. Variations such as "football scoring" (3 points for a win, 1 point for a draw) may be used by tournament organizers, but ratings are always calculated on the basis of standard scoring. A player's score may be reported as total score out of games played (e.g. 5½/8), points for versus points against (e.g. 5½–2½), or by number of wins, losses and draws (e.g. +4−1=3).
