The two-player game of chess is played with 32 pieces on a 64 square checkerboard, 8 squares along each side and 16 pieces for each player.
Basic movement rules for chess
A game of chess features six types of pieces. Listed below are the different movement rules for official chess.
1. King (one per side)
The king can move in all directions, though only one square at a time.
2. Queen (one per side)
Much like the king, the queen can move in any direction, but she can move as far as she wants. She cannot jump over other pieces though.
3. Bishop (two per side)
The bishop can move as far as he wants, but only diagonally. This means that a bishop can never end up on a field that isn't the same colour as the one he started the game out on. He can't jump over other pieces.
4. Knight (two per side)
The knight, called a horse by some, is the only piece that can jump over other pieces. The knight has a somewhat peculiar movement pattern, as it essentially moves in an L-shape.
5. Rook (two per side)
The rook can moves as far as it wants, and it always moves in a straight line, horizontally or vertically. It cannot jump over other pieces.
6. Pawn (eight per side)
In it's starting position, the pawn can move either one or two spaces straight ahead. However, once a pawn has moved, it can only move one space straight ahead. Under no circumstance can a pawn move backwards. The pawn also has a special pattern to take other pieces. To take a piece, a pawn must move diagonally forward. If a piece is directly in front of it, the pawn cannot take it.
Strategy and advanced rules for chess
When a piece captures an opposing piece, the opposing piece is removed from the board.
When the king is placed in jeopardy by a piece that could capture it, it is "in check", and the next move must be to escape or avoid check.
When the king is in check and has no escape, the game is over.
Upon reaching the 8th rank of the chess board (ie. the top of the board, the opponent's side), a pawn may be promoted and replaced by any other piece of the player's choosing except a king. This is typically the queen, due to its power, but may also be a rook or other piece. There is no restriction on how many similar promoted pieces may exist, including multiple queens to a theoretical maximum of 9.
A method for protecting the King. If neither the king and a rook have moved, and there is no obstructing piece, they may hop over each other and effectively switch places. Splitting the difference in the left (queenside) or right (kingside) half of the board.
The rule that a pawn may move two squares from its starting location, is countered by the ability of an approaching pawn to capture it as though it had only moved one square.
Chess is believed to have originated in northwest India during the Gupta Empire, where its early form in the 6th century was known as chaturaṅga (four divisions [of the military] – infantry, cavalry, elephants, and chariotry, represented by the pieces that would evolve into the modern pawn, knight, bishop, and rook, respectively). According to both Chess historians Gerhard Josten and Isaak Linder "the early beginnings" of chess can be traced back to the Kushan Empire based around what are today Pakistan and Afghanistan. The earliest evidence of chess is found in the neighboring Sassanid Persia around 600, where the game came to be known by the name chatrang. Chatrang is evoked in three epic romances written in Pahlavi (Middle Persian). Chatrang was taken up by the Islamic world after the Muslim conquest of Persia (633–644), where it was then named shatranj, with the pieces largely retaining their Persian names. In Spanish "shatranj" was rendered as ajedrez ("al-shatranj"), in Portuguese as xadrez, and in Greek as ζατρίκιον (zatrikion, which comes directly from the Persian chatrang), but in the rest of Europe it was replaced by versions of the Persian shāh ("king"), which was familiar as an exclamation and became the English words "check" and "chess". Murray theorized that Muslim traders came to European seaports with ornamental chess kings as curios before they brought the game of chess.
The game reached Western Europe and Russia by at least three routes, the earliest being in the 9th century. By the year 1000, it had spread throughout Europe. Introduced into the Iberian Peninsula by the Muslim Moors in the 10th century, it was described in a famous 13th-century manuscript covering shatranj, backgammon, and dice, named the Libro de los juegos.
Indian chess (chaturanga) arrived in East Asia slightly before the arrival of Persian chess (shatranj) in Europe. In China, some time by the 8th or 9th century, Indian chess had evolved into xiangqi, or Chinese chess. From there, it evolved into janggi in Korea and shogi in Japan within the next several centuries.
Chess was hugely important to the foundation of video games.
The first example of what could today be called a computer game was based on chess. Alan Turing, a British mathematician, developed a theoretical computer chess program as an example of machine intelligence. In 1947, Turing wrote the theory for a program to play chess. His colleague Dietrich Prinz wrote the first limited program of chess for Manchester University's Ferranti Mark I in November 1951. The program was only capable of computing "mate-in-two" problems and was not powerful enough to play a full game. Input and output were offline, with no "video" involved, but it was a precursor to what would later be known as video games.
Chess was also the foundation for wargaming, which in turn laid the foundations for the strategy and RPG genres in video games.