Last modified on October 15, 2023, at 05:32


A typical chess set and tournament clock.

Chess is an intellectually challenging game of chivalry between two players. Based purely on skill without any element of chance, chess has long been one of the most popular games in the world, and today chess is played by upwards of 800 million people worldwide. On Feb. 2, 2023, was the #1 free app on iOS in 28 countries. Chess sharpens the mind, improves decision-making skills, helps overcome addiction and procrastination, drives out anxiety, and builds character. Promoters of chess include Benjamin Franklin,[1] Thomas Jefferson, actors Humphrey Bogart and Arnold Schwarzenegger, actress Marilyn Monroe, and movie producer Stanley Kubrick.[2] Rock stars who were good chess players include the blind Ray Charles and Willie Nelson. See Chess Players.

Chess can be helpful in overcoming addictions exploiting images or patterns, including pornography, gambling, video games, and televised football. Chess fills the mind with a healthy activity while reinforcing the devastating consequences ("checkmate") of bad decisions.[3] Temerity is punished in chess, as is timorousness. Chess seems to fend off obesity, unlike unhealthy hobbies; almost no top chess players are obese despite the game's sedentary nature.

Many women play and benefit from chess, charmingly elevating it as an art form in popular streaming commentaries on such as[4] While virtually all the top tournament chess players are male, and only about 1% of the 1500 grandmasters are female, many of the top chess streaming shows are hosted by women.

Chess emphasizes individualistic pieces, in contrast to more collectivist strategy game called "go". Chess is more hierarchical, more militaristic, and more clear-cut when someone wins. "Go", which is ancient Chinese incrementalist-type of board game, has far fewer decisive moves than in chess. "Go" tournaments feature almost entirely Asian players, while the top chess players are typically from the West or from India.

Chess is nearly unique among games in having no element of chance and requiring a high degree of foresight and anticipation of an adversary's strategy. In competitive chess, a timer is used such that quick processing of information is advantageous, particularly at high skill levels.

One of the greatest chess players ever, Paul Morphy of New Orleans, played in the mid-1800s and refused to wager on his games even though gambling on chess was common then, and even though he often won stunning victories unexpected at his young age.

Modern international chess has a powerful, sweeping queen who was not a piece provided in the original game. The long reach of bishops today was also lacking at first. Maneuvers such as castling or capturing en passant have been developed within the past few hundred years.

Today, chess is one of the most popular board games in the world. International competitions, including world championship events, are organized by an organization called FIDE and American competition organized by the USCF (United States Chess Federation). The only American world champion was Bobby Fischer, although Paul Morphy of Louisiana was likely the strongest player in the world in the 1850s, before a formal world champion was determined. The current World Chess Champion is Norwegian Magnus Carlsen. Prior to that, the world champion was Indian Viswanathan "Vishy" Anand.

Chess and and increasing mental performance

See also: Chess and increasing mental performance

Chess presents interesting intellectual challenges. It is said that: "Chess has an advantage over most school subjects: it combines both theory and practice. Ideas are honed and tested in the crucible of competitive play. Poor formulation or poor execution of ideas loses games. Careless, faulty thinking is ruthlessly refuted on the chessboard."[5]

According to "Playing chess can improve cognitive skills like memory, planning, and problem-solving. It may also help reduce symptoms of certain brain conditions.[6]

Some countries, particularly nations like Uzbekistan from the former Soviet Union, promote chess as a fundamental aspect of learning and mental development.

Online Chess

Online chess that allows longer games without chess time clock:


Sir Lawrence Alma Tadema, Egyptian Chess Players, 1865.

Modern chess is based on the Holy Roman Empire, originating in the A.D. 1300s with bishops and knights as pieces and advanced moves like castling and pawn conversion available today. Perhaps to deny its Christian-affiliated roots, chess is attributed by some to India, where a game called Shaturanga was played. The earliest extant description of the game is contained in the Bhavishya Purana, which dates from A.D. 300 to A.D. 600. Shaturanga used dice, but Hinduism bans gambling. As a result, a game of chess developed free from any dice or chance. The exact rules of Shaturanga are not known, but the game developed further in Persia into something similar to its modern form. The Persian game Shatranj - which remains popular in the middle east today - is nearly identical to modern chess. By A.D. 1200 the game reached southern Europe, and in the late fifteenth century the Europeans adopted a number of changes: the queen, which had formerly been a very weak piece, became the strongest piece on the board, and allowing pawns to move two squares on the first move became standard. These changes had the effect of speeding up play, and they brought the game into the form we know today.

In the 1500s castling was introduced into the game, which made attacks on the king far more difficult. Some grandmasters lament that change.

There has been some speculation that chess has roots in China. It's clear that chess is in some way related to XiangQi (Chinese Chess) and Shogi (Japanese Chess which is played on a 9x9 rather than 8x8 board), but scholars disagree about whether either of these variants predates Shaturanga.

The Board

The chess board is a square, divided into 64 smaller squares arranged in eight rows of eight. The squares are alternating light and dark, with a light square in the bottom right hand corner.

The horizontal rows of squares are referred to as "ranks" and the vertical rows are referred to as "files". The goal of the game is to place the opposing king into checkmate, that is, a position in which the king is under attack but cannot escape.


Staunton Style chess pieces. From left to right: King, Queen, Bishop, Knight, Rook, and Pawn.

Each player has a total of 16 pieces; 8 pawns, 2 knights, 2 bishops, 2 rooks, 1 queen, and 1 king.

Relative Value of Pieces

There are several different ideas about the relative value of the pieces. It is important to note that the "points" used to assign a value to each piece are hypothetical and do not constitute a score; they are merely an attempt to quantify the relative power that each piece can hypothetically exert upon the board.

The method most often used is:

  • Chesspawn.jpg Pawn—1
  • Chessknight.jpg Knight—3 (some say 2.5, as Knights are generally regarded as slightly inferior to Bishops in many middlegame and endgame situations)
  • Chessbishop.jpg Bishop—3
  • Chessrook.jpg Rook—5
  • Chessqueen.jpg Queen—9
  • Chessking.jpg King—Priceless, since its loss means the loss of the game. However, as an active piece in the endgame it is usually considered to have a value of 3.

(The value to the player of some pieces will actually vary during the course of the game, for instance, in an endgame, the King has an attacking power of about 3)


The most popular style of pieces are known as Staunton style pieces, the tournament standard for chess pieces, although other types exist. Often, popular themed chess sets will appear with characters from popular culture or fiction taking the places of the more common Staunton style pieces. These novelty pieces are not tournament sanctioned however, and can sometimes cause confusion during game play as to which piece is which.

Although chess pieces can come in a variety of materials, marble and glass tend to be very popular, but for most chess tournaments, simple plastic pieces are usually favored. Also, while many home chess sets use heavy boards made out of wood or stone or some polymer material, tournament boards are actually roll-able mats with the board printed on it.


The object of the game is to checkmate the other player's King before he checkmates your king. When a pawn reaches the far side of the board, it may be promoted to any other piece (except a King).

  • The player with the White pieces always moves first.
  • The players alternate moving until the game has ended.

Initial Conditions

The pieces are put on the board in each player's side as follows:

  • In the first row from left to right (with the leftmost square being black): rook, knight, bishop, queen, king, bishop, knight and rook.
  • The second row is filled with pawns.


The pieces move as follows.

  • The pawn moves one square forward, except when moving from its opening position, when it can optionally move two. The pawn is the only piece that captures in a way different from the way it moves. It captures opposing pieces by capturing one square diagonally forward. When another piece is on the square directly in front of a pawn it cannot move unless it is making a capture.
  • The knight, which is the only piece that can jump over other pieces, moves one square in one straight direction and two in the other (essentially, in an "L" shape).
  • The bishop can move as many squares as desired diagonally.
  • The rook can move as many squares as desired in a straight direction.
  • The queen is the most powerful piece in the board. It can move as many squares as desired (without jumping over another piece), either straight or diagonally.
  • The king, which is the most important piece on the board, moves one square, either straight or diagonally.


All pieces except for the pawn capture along their lines of motion. A capture is made by moving a piece to a square occupied by one of the opponent's pieces, and removing the opponent's piece from the board. If a piece can move to occupy the location of an opponent's piece, it can capture that piece. The pawn, can only capture by moving diagonally forward one square. A piece is said to be undefended if it has no piece "supporting" its position - i.e., preventing an opponent from capturing it by threat of losing his attacking piece.

Special Moves

  • Castling- When a player has no pieces between a rook and his king, and he has not moved either piece, he can move the king two squares in the direction of the rook, and then place the rook on the square that the king passed over. A player cannot castle if the King is currently in check, would be in check after castling, or would move through a square which is under attack.
  • en passant- French for "In passing." In chess, if a player pushes his pawn far down to the end of the board, and his opponent pushes a starting pawn 2 spaces ahead, to put the pawn on the same row to avoid confrontation, the player may choose to invoke the "en passant" move, which treats the enemy pawn as though it had only moved one space. The player may capture diagonally on the square behind the enemy pawn, and remove the enemy pawn. The principle is that the two space rule for a pawn's first move cannot be used to avoid confrontation between two pawns. However, the player may only invoke "en passant" on the first turn after the opponent pushes his pawn. He cannot make it after that turn.

The end of the game

A chess game may end in a number of ways.

  • Checkmate: The winning player checkmates his opponent's King (see below).
  • Resignation: The losing player, facing an inevitable future checkmate, resigns rather than play out an extended series of hopeless moves. A player may indicate resignation by toppling his king on its side.
  • Loss on Time: In games with a time limit, a player may lose by failing to make a time control, causing his clock to run out.
  • Draw: The game may end in a draw, in which case neither player wins.


Checkmate is achieved when the following conditions are met.

  • The King is in check; that is, it is directly attacked by an opponent's piece.
  • Every square that the King can move to is also attacked by an opponent's piece.
  • The Piece that is attacking the King cannot be captured.
  • Another Piece cannot be interposed between the attacking piece and the King to block the check.

When a King is checkmated, the game is over, and the player initiating the checkmate is the winner.


There are several ways that the game can end in a draw.

  • Stalemate: A player is said to be stalemated when he cannot make a legal move, and is not in check.
  • Draw by agreement: The players mutually agree to a draw. In competitive chess, a player may make a draw offer after he has made his move, but before he has started his opponent's clock.
  • Draw by repetition: Either player may claim a draw if the same position has appeared on the board three times. The three occasions need not be consecutive.
  • 50 move rule: Either player may claim a draw if fifty moves have transpired without a capture or a pawn move.


Chess notation is used to record the moves of a chess game. This has several uses. Notation can be used to record games for review at a later time. There are two major methods of chess notation, Algebraic and Descriptive.

For all forms of Notation

The notation for a chess game is taken like this. At the top of the page are the players — white listed first — with their names under their colors. Numbers go down the left side of the page to indicate the move number. (see below)

    White,   Black
Name Name 1.

Moves are recorded in columns, separated by commas.

Space is usually allotted on the top of tournament scoresheets to record the date and location of the game, and sometimes to record the time limit and opening name.


Each piece is designated by its corresponding letter as follows:
K = King
Q = Queen
R = Rook
B = Bishop
N = Knight (notice 'K' is reserved for the King)
P = Pawn

(In strict chess parlance, the pawns are not considered pieces; officially, a standard chess set consists of sixteen pieces and sixteen pawns.)

-       Moves to
x       Captures
+       Check
++      Checkmate
0-0     Castles king-side
0-0-0   Castles queen-side
e.p.    en passant
/       to indicate which square a piece moved from (only when needed to clarify)
/Q      Pawn promotion. (use /Q for queen, /R for rook, etc.)
!       A good move
!!      A very good move
!?      An interesting move
?!      A dubious move
?       A questionable move
??      A blunder


Algebraic is the most commonly used method of notation.

The Board

In algebraic notation, each file is assigned a letter, and each rank is assigned a number. Each square is designated by the letter and number from its rank and file. a1 is the square in the bottom left corner for the white player.


Moves are recorded by indicating the piece to be moved and the square it is to be moved to, sometimes using a hyphen (-). For example, if white wants to move his Kingside Knight towards the center of the board to start the game, the notation would be:

   White  Black 
1. Nf3,  ....


   White  Black 
1. N-f3,  ....

In algebraic notation, a P is not used to indicate the pawn. A pawn move is implied when no piece is indicated. So if white wants to advance his king pawn 2 squares, and black responds by advancing his king pawn 2 squares, the notation would be:

   White  Black 
1. e4,    e5,
2. ....

Occasionally, two pieces of the same type can move to the same square. To eliminate ambiguity, the unique rank or file of the moving piece is identified after the piece symbol. For example, suppose both of Black's Rooks are on the 8th rank (on the squares f8 and a8), and there are no pieces in between them. Black moves the f8 Rook to d8. In other circumstances, the move would be annotated

17. ....    Rd8

but because either Rook could have moved to d8, the identifying file for the f8 Rook must be included, as in

17. ....    Rfd8


Captures by a piece or pawn are indicated by first transcribing the symbol for the piece performing the capture, followed by an 'x', followed by the square the capturing piece or pawn moved to. For example, if White uses his Queen to capture a piece on the square h7 on move 23, the correct notation is

23. Qxh7,    ....

Because pawns are not designated with a symbol, the system is slightly different for pawn captures. The file originally occupied by the pawn is used to identify the pawn performing the capture. If a black pawn on e5 captures a white piece or pawn on d4 on move 5, the notation is

5. ....,    exd4


In the more archaic descriptive notation, squares are described according to the starting piece positions. The square originally occupied by the Rook on the Queenside is referred to as "Queen's Rook One" (QR1), while "Queen's Rook Four" is the square directly in front of the Queen's Rook on the fourth rank. Thus, a typical opening move is described as "Pawn to King Four", and is written as

1. P-K4,    ....

Note that in descriptive notation, pawns have the designation 'P'. The notation's disadvantages become apparent over the course of a complex game, especially because the same square has different names depending on the perspective of the White and Black pieces. King's Bishop Three (KB3) for White is King's Bishop Six (KB6) for Black.

Captures in descriptive notation operate similar to algebraic notation; for example,

45. ....    R-xQN7

means that on his 45th move, Black captured a piece or pawn on his Queen's Knight Seven square (the b2 square in algebraic notation).

Although this method of recording is seldom used, it is advisable for new players to be familiar with it because many older text books use it.

Tactics and strategy

See also: Chess strategies

Chess players often refer to shorter, forcing sequences of moves that lead to clear advantages as tactics, while moves designed to create or nurture long-term advantages are called strategic.

For more information on specific tactics, see chess tactics. For more information on specific strategic themes, see chess strategies.

Chess Variants

There are a number of games based on chess with rule variations, and these are referred to as chess variants. One of the most popular of these is Bughouse, a partner-based game in which a player who captures his opponent's piece can give it to a partner on another board to drop on a square of his choosing. Another is Kriegspiel, a game in which a player can see his pieces but not that of his opponent.[7] A simpler variant is Antichess, which is also called Suicide chess, in which a player must make a capturing move if any legal captures exist on the board, and in which the goal is to run out of pieces first.

In 1996, Bobby Fischer introduced a variant called FischerRandom Chess, which involves scrambling the positions of the pieces on the first and eighth ranks before starting play. A number of rules govern the precise manner in which the pieces can be arranged; for example, the king must be somewhere between the two rooks, so that castling to either side is still possible, and the black and white positions must mirror one another. The rules provide for 960 possible starting positions, and for this reason the game is sometimes called Chess960. Fischer hoped his variant would encourage creative thinking and avoid the memorization associated with opening play in modern chess.

The 20 40 40 rule of learning chess for chess players who are not chess experts

See also: Chess mastery and memory improvement and Chess and increasing mental performance

The 20-40-40 rule in chess is a rule for players having a below International Chess Federation (FIDE) ranking of 2000 (below Chess Expert level) and it states that 20% of your study should be dedicated to openings, 40% to the middlegame, and 40% to the endgame.[8][9][10]

Computer Chess

Deep Blue, a computer developed by IBM, was the first computer engine to beat a human world champion in 1997, when it defeated Garry Kasparov in a six-game series. This series was a rematch of 1996 series which Kasparov won, although Deep Blue had been upgraded since the first series. It should be noted that during this second match, Deep Blue was also upgraded between games to avoid falling into the same type of trap more than once.

Chess engines have increased in strength in recent years to the point where humans are falling behind. In 2005, Michael Adams, one of the top fifteen players in the world, played a six-game match against the engine Hydra, and lost five games with only one draw. Chess writer Eric Schiller, who uses computer assistance in writing his books, admits that "computers have taken some of the fun out of (chess)." Despite this, chess remains far from being a solved game.

Words from Chess

  • check (noun, origin in 1400s)
  • checkmate (origin in the 1300s)
  • endgame (origin in 1884)
  • gambit (origin in 1656)
  • jeopardy (origin in the 1300s)
  • stalemate (origin in 1765)

Rankings in Chess

The four basic levels of high skill in chess are, in this order of ranking:

  • Grandmaster ("GM")
  • International Master ("IM") as recognized by FIDE (the International Chess Federation, known by the acronym for its French name, the Federation Internationale des Echecs)
  • FIDE Master ("CM")
  • Candidate Master ("CM")

Chess mastery and memory improvement

Bobby Fischer playing chess against Boris Spassky in 1974.

See also: Chess mastery and memory improvement and Chess and increasing mental performance

In his article Memory and Chess, Bill Wall wrote:

Studies of chess players have confirmed that the ability to memorize board positions was one of the best overall indicators of how good a chess player is.

To the average person, playing a game of chess without sight of the board represents an extremely difficult, if not impossible challenge for the memory. No other human memory feat can surpass the achievements of the best simultaneous blindfold players. Blindfold chess players need knowledge and experience, imagination, and memory. Masters who were tested in blindfold games were generally able to remember all the moves played in a sequence of blindfold games. Masters differed on whether they used visual or abstract imagery to represent the chess board. The majority of masters said that they used only an abstract representation, combined with sub vocalizations of previous moves, to mentally examine the board.

In 1881, an article called "Memory in Chess Playing," appeared in Scientific American. It stated that wonderful as are the feats of chess-players who can work out a game or a series of games without seeing the board, there is nothing really remarkable in them. When once mastered, the trick is not only fairly easy of performance, but the fact that the process is purely mental rather facilitates than impedes the action of the mind. To the "blindfold" chess player, there is present a mental picture of the board with the pieces in position. He can change the position of the men as easily as he can think, and after he has mastered the difficulty of fixing the mental picture, it is distinctly before him. As a rule, chess-players are mental-picture-readers, and can at pleasure call up any one of several pictures of boards as they last conceived them. The most difficult feat is to play two or three games simultaneously blindfold, the moves made by their opponents being told them in close sequence and their own moves being directed after all the reports of the proceedings of their opponents have been received. (source: Scientific American, Dec 10, 1881, Vol. 45, # 24, p. 378)

In 1893 and 1894, Alfred Binet (1857-1911) conducted perhaps the first psychological studies into chess. He investigated the cognitive facilities of chess masters who could play blindfold chess. He hypothesized that chess depends upon the phenomenological qualities of visual memory. He found that only chess masters were able to play chess successfully without seeing the board and intermediate players found it impossible to play a game of blindfold chess. Binet found that experience, imagination, and memories of abstract and concrete varieties were required in master chess.[11] notes:

Chess is a mental battleground where strategic prowess and memory go hand in hand. A strong memory is essential for recalling opening lines, calculating variations, and making informed decisions...

A strong memory not only aids in recall but also influences your strategic decision-making, helping you outwit opponents and formulate winning plans. As you continue your journey in the world of chess, remember that honing your memory skills is not only a path to success but also a profound way to appreciate the intricate interplay of strategy and memory that defines this timeless game.[12]

Articles on improving one's chess game via memory improvement techniques and strategies

Journal articles on improving one's chess game via memory improvement techniques

Journal articles on chess and mnemonics

See also: Mnemonic

A mnemonic device (memory device), is any learning technique that assists someone's memory.

The human brain is the most complex physical entity in the universe.[14][15][16]

Books on chess

Chess vs. Go

See also: Go (game)

While chess is extremely popular strategic and tactical game in the Western World, Go is more popular in the Eastern World.

David Lai wrote on the difference between chess and go:

The philosophy behind chess is to win decisively. For the winner, victory is absolute, as is defeat for the loser. In chess, both players have the same clear and overriding objective―capturing the opposing king―and accomplish this objective by decimating whatever opposing forces are standing in the way. In go, total victory usually happens between two mismatched players. That kind of victory, as Sun Tzu puts it, is not the pinnacle of excellence. In a go game between two well-matched players, the margin between win and lose is usually very small, often decided by only a few points. The philosophy behind go therefore is to compete for relative gain rather than seeking complete annihilation of the opponent’s forces. It is dangerous to play go with the chess mindset. One can become overly aggressive so that he will stretch his force thin and expose his vulnerable parts in the battlefields.

In chess, the focus is on the king. All the moves are geared toward checking the king. In designs to capture the king, chess players always try to eliminate the powerful pieces such as the queen, knight, castle, and bishop. Chess players typically focus on these powerful military units as the ‘center of gravity’ and ‘decisive point’ (in Clausewitz and Jomini’s terms). Naturally, chess players are single-minded. In go, it is a war with multiple campaigns and battlefields. There is no one single focus on the board. A go player must always keep the whole situation in mind. Attacking the opponent’s strategy therefore is much more appropriate in go. As a prolonged and complex game, go players focus on building or creating rather than chess players’ emphases on removal and destruction.” [17]

Another major difference between chess and go is that in go matches there is always a winner and a loser without any draws.

See also

External links

  • FIDE - International Chess Federation based in Switzerland, which posts rankings of players in multiple categories
  • USCF - United States Chess Federation
  • ICCF - International Correspondence Chess Federation
  • ACP - Association of Chess Professionals
  • FICS - Free Internet Chess Server

Online chess: