Chess

From WikiChess

Chess is a zero sum, competitive, perfect information game. Chess is one of the most popular games, worldwide played in clubs, tournaments, by correspondence, on the Internet or informally. The game is played on a chequered board with 64 squares, arranged in a eight-by-eight square, the chessboard. The two players control each one a set of sixteen pieces, white or black colored. The object of the game is to checkmate the opponent's king, whereby the king is under immediate attack (in "check") and there is no way to remove it from attack on the next move.

Contents 1 History 2 Rules 2.1 General 2.2 Check and Checkmate 2.3 Pawn 2.3.1 Setup 2.3.2 Movement 2.3.3 Capturing 2.3.4 Special Moves 2.3.4.1 Promotion 2.3.4.2 En passant 2.4 Bishop 2.4.1 Setup 2.4.2 Movement 2.5 Knight 2.5.1 Setup 2.5.2 Movement 2.6 Rook 2.6.1 Setup 2.6.2 Movement 2.7 Queen 2.7.1 Setup 2.7.2 Movement 2.8 King 2.8.1 Setup 2.8.2 Movement 2.8.3 Castling 3 Material Values 4 Basic Strategy

[edit] History

Chess is believed to have originated in India 1,400 years ago, as this was the earliest finding of chess pieces. However, artifacts that bear a resemblance to chess pieces have been found in Italy. Therefore, the true date is unknown.

Chaturanga was the name of the game that the people of India played. When Buddhists came as missionaries to India, they took the game with them. Chaturanga continued to move through the countries, sometimes having it's name changed. When Persia received the game, it was named chatrang. Arabs conquered Persia and took their game, renaming it to shatrang. Spain and Sicily then got the game and brought it to western Europe. In Europe, shatrang became widely popular. During the Europian control of shatrang, its rules were changed. The queen and bishops were added to the boards, as the India version of the game had neither of these. In order to add excitement to the game, they added the rule of promotion. This new game became even more popular in Europe. In the nineteenth century, America learned of this great game. But even today, chess continues to be a widely popular game around the world.

[edit] Rules

This is a rough explanation of the rules of chess. While it does not delve into strategy, it is enough to get you started.

[edit] General

The player using the white pieces moves first in Chess, then a move is made by the player of the black pieces. Each player is obligated to move on their turn. If it is not possible to make a legal move, stalemate has been achieved, which is a drawn game. The goal of chess is to checkmate your opponent's king. Draws can also occur through the fifty move rule, stalemate or threefold repetition. If neither player has enough material to checkmate the opponent, the game is therefore declared a draw.

[edit] Check and Checkmate

A check is an immediate threat to capture the king. A king so threatened is said to be in check. In the following move, the player whose king is in check must get his king out of check, if it is possible. Either the threat must be stopped (by interposing a piece between the threatening piece and the king, or by capturing the threatening piece) or the king must be moved to a space where it is no longer in check. If the king is in check and there is no legal move which gets the king out of check, the king is said to be checkmated and the game is over. The player whose king is checkmated loses and the opposing player wins the game. In this usage, the words "check" and "chess" come via Arabic from Persian shāh, meaning "king"

There are six kinds of pieces in chess: the queen, the king, the rook, the bishop, the knight, and the pawn. (Technically the definition of piece does not include the pawn).

[edit] Pawn

The pawn is the less powerful piece in chess, however it can promote to any other piece advancing all the way to the opposite side of the board. (see Special Moves below).

[edit] Setup

The eight pawns are set on rows two and seven, as shown to the left.

[edit] Movement

Pawns are unusual in movement and use. Unlike all the other pieces, pawns may not move backwards. Normally a pawn moves by advancing a single square, but the first time each pawn is moved from its initial position, it has the option to advance two squares. Pawns may not use the initial two-square advance to jump over an occupied square, or to capture. Any piece directly in front of a pawn, friend or foe, blocks its advance.

[edit] Capturing

Unlike other pieces, the pawn does not capture in the same way as it moves. A pawn captures diagonally, one square forward and to the left or right.

[edit] Special Moves

The pawn has two "special" moves: En Passant and Promotion.

[edit] Promotion

A pawn that advances all the way to the opposite side of the board (the opposing player's first rank) is promoted to another piece of that player's choice of a queen, rook, bishop, or knight of the same color. The pawn is immediately (before the opposing player's next move) replaced by the new piece. The choice of promotion is not limited to captured pieces: players may have as many as ten knights, ten bishops, ten rooks or nine queens. In game 11 of their 1927 world championship match, José Raúl Capablanca and Alexander Alekhine each had two queens in play at once.

[edit] En passant

An even more unusual move is the en passant capture. This arises when a pawn uses its initial-move option to advance two squares instead of one, and in so doing passes over a square that is attacked by an enemy pawn. That enemy pawn, which would have been able to capture the moving pawn had it advanced only one square, is entitled to capture the moving pawn "in passing" as if it had advanced only one square. The capturing pawn moves into the empty square over which the moving pawn moved, and the moving pawn is removed from the board. The option to capture en passant must be exercised on the move immediately following the double-square pawn advance, or it is lost and may not be made later.

[edit] Bishop

[edit] Setup

The bishop is placed on the third column and sixth column of the first and eighth row.

[edit] Movement

The bishop has no restrictions in distance for each move, but is limited to diagonal movement. Bishops cannot jump over other pieces. A bishop captures by occupying the square on which an enemy piece is staying, but it cannot capture nor move trough a piece on its own side.

[edit] Knight

[edit] Setup

Knights are placed on the first and eighth row, on the second and seventh columns.

[edit] Movement

The knight move is unusual among chess pieces. When it moves, it can move two squares horizontally and one square vertically, or two squares vertically and one square horizontally. The complete move therefore looks like the letter 'L'. Unlike all other standard chess pieces, the knight can 'jump over' all other pawns and pieces (of either colour) to its destination square. It captures an enemy piece by moving into its square, but it cannot move in the same square of a piece on its own side.It moves in an L shape as 2 and 1 or 1 and 2.

[edit] Rook

[edit] Setup

Rooks are set on the first and eighth row, on the first and eighth column.

[edit] Movement

The rook moves horizontally or vertically, forward or back, through any number of unoccupied squares. Like other pieces, it captures by occupying the square on which an enemy piece stands. The rook also participates, along with the king, in a special move called castling. It cannot capture nor move trough a piece on its own side.

[edit] Queen

[edit] Setup

The queens are set up on the first and eighth column, and on the fourth column.

[edit] Movement

The queen can be moved any number of unoccupied squares in a straight line vertically, horizontally, or diagonally, thus combining the moves of the rook and bishop. The queen captures by occupying the square on which an enemy piece sits. It cannot capture nor move trough a piece on its own side.

[edit] King

[edit] Setup

The king is placed on the first and eighth row and on the fifth column.

[edit] Movement

A king can move one square in any direction (horizontally, vertically, or diagonally). The exceptions to this rule are that it may not move onto a square that is threatened by an enemy piece, or one that is already occupied by another piece on its own side. As a result, the opposing kings may never occupy adjacent squares. As with all pieces except the pawn, it captures by moving onto a square occupied by an enemy piece.

[edit] Castling

In conjunction with a rook, the king may make a special move called castling, in which the king moves two squares toward one of his rooks and then the rook is placed on the other side of the king. Castling consists of moving the king two squares on its first rank toward either one of the original rooks, then moving the rook onto the square over which the king crossed. Castling is allowed only when neither the king nor the castling rook has previously moved, when no squares between them are occupied, when the king is not in check, and when the king will not move across or end its movement on a square that is under enemy control.

[edit] Material Values

Deciding who is "winning" or "losing" in chess cannot be left to the sheer numbers of pieces on the board; each piece has a distinct value, measured in centipawns. The centipawn is a unit of measure used in chess, equal to 1/100 of a pawn, so 100 centipawns = 1 pawn. Calculations of the value of pieces provide only a rough idea of the state of play. The exact piece values will depend on the game situation, and can differ considerably from those given here. In some positions, a well-placed piece might be much more valuable than indicated by heuristics, while a badly-placed piece may be completely trapped and, thus, almost worthless. Also, values does not include tactical (positional) factors, which may very important in a game. Usual values are as follows:

- Queen 900
- Rook 500
- Knight 300
- Bishop 300
- Pawn 100

See centipawn for more informations about the material value of the chess pieces.

[edit] Basic Strategy

Chess strategy is concerned with evaluation of chess positions and with setting up goals and long-term plans for the future play. During the evaluation, players must take into account the value of pieces on board, pawn structure, king safety, space, and control of key squares and groups of squares (for example, diagonals, open-files, and dark or light squares). Another important factor in the evaluation of chess positions is the pawn structure (sometimes known as the pawn skeleton), or the configuration of pawns on the chessboard. Being the least mobile of the chess pieces, the pawn structure is relatively static and largely determines the strategic nature of the position. Weaknesses in the pawn structure, such as isolated, doubled or backward pawns and holes, once created, are usually permanent. Care must therefore be taken to avoid them unless they are compensated by another valuable asset (for example, by the possibility to develop an attack).