HAL 9000 is a fictional artificial intelligence character and the main antagonist in Arthur C. Clarke's Space Odyssey series. First appearing in the 1968 film 2001: A Space Odyssey, HAL is a sentient artificial general intelligence computer that controls the systems of the Discovery One spacecraft and interacts with the ship's astronaut crew. While part of HAL's hardware is shown toward the end of the film, he is mostly depicted as a camera lens containing a red and yellow dot, with such units located throughout the ship. HAL 9000 is voiced by Douglas Rain in the two feature film adaptations of the Space Odyssey series. HAL speaks in a soft, calm voice and a conversational manner, in contrast to the crewmen, David Bowman and Frank Poole.
Algebraic notation is the standard method for recording and describing the moves in a game of chess. It is based on a system of coordinates to uniquely identify each square on the board. It is used by most books, magazines, and newspapers.
Descriptive notation is a chess notation system based on abbreviated natural language. Its distinctive features are that it refers to files by the piece that occupies the back rank square in the starting position and that it describes each square two ways depending on whether it is from White or Black's point of view. It was common in English, Spanish and French chess literature until about 1980. In most other languages, the more concise algebraic notation was in use. Since 1981, FIDE no longer recognizes descriptive notation for the purposes of dispute resolution, and algebraic notation is now the accepted international standard.
This glossary of chess explains commonly used terms in chess, in alphabetical order. Some of these terms have their own pages, like fork and pin. For a list of unorthodox chess pieces, see Fairy chess piece; for a list of terms specific to chess problems, see Glossary of chess problems; for a list of named opening lines, see List of chess openings; for a list of chess-related games, see List of chess variants; for a list of terms general to board games, see Glossary of board games.
The fifty-move rule in chess states that a player can claim a draw if no capture has been made and no pawn has been moved in the last fifty moves. The purpose of this rule is to prevent a player with no chance of winning from obstinately continuing to play indefinitely or seeking to win by tiring the opponent.
The Immortal Game was a chess game played in 1851 by Adolf Anderssen and Lionel Kieseritzky. It was played while the London 1851 chess tournament was in progress, an event in which both players participated. The Immortal Game was itself a casual game, however, not played as part of the tournament. Anderssen won the game by allowing a double rook sacrifice, a major loss of material, while also developing a mating attack with his remaining minor pieces. Despite losing the game, Kieseritzky was impressed with Anderssen's performance. Shortly after it was played, Kieseritzky published the game in La Régence, a French chess journal which he helped to edit. In 1855, Ernst Falkbeer published an analysis of the game, describing it for the first time with its namesake "immortal".
Checkmate is any game position in chess and other chess-like games in which a player's king is in check and there is no possible escape. Checkmating the opponent wins the game.
In chess, the fool's mate is the checkmate delivered after the fewest possible moves from the game's starting position. It arises from the following moves, or similar:
In chess, a back-rank checkmate is a checkmate delivered by a rook or queen along the opponent's back rank in which the mated king is unable to move up the board because the king is blocked by friendly pieces on the second rank.
In chess, en passant describes the capture by a pawn of an enemy pawn on the same rank and an adjacent file that has just made an initial two-square advance. The capturing pawn moves to the square that the enemy pawn passed over, as if the enemy pawn had advanced only one square. The rule ensures that a pawn cannot use its two-square move to safely skip past an enemy pawn.
Chess notation systems are used to record either the moves made or the position of the pieces in a game of chess. Chess notation is used in chess literature, and by players keeping a record of an ongoing game. The earliest systems of notation used lengthy narratives to describe each move; these gradually evolved into more compact notation systems. Algebraic notation is now the accepted international standard, with several variants. Descriptive chess notation was used in English- and Spanish-language literature until the late 20th century, but is now obsolescent. Portable Game Notation (PGN) is a text file format based on English algebraic notation which can be processed by most chess software. Other notation systems include ICCF numeric notation, used for international correspondence chess, and systems for transmission using Morse code over telegraph or radio. The standard system for recording chess positions is Forsyth–Edwards Notation (FEN).
The Damiano Defence is a chess opening beginning with the moves:
- e4e5
- Nf3f6?
A selfmate is a chess problem in which White, moving first, must force the unwilling Black to deliver checkmate within a specified number of moves. Selfmates were once known as sui-mates.
The Saavedra position is one of the best-known chess endgame studies. It is named after the Spanish priest Fernando Saavedra (1849–1922), who lived in Glasgow during the late 19th century. Though not a strong player, he spotted a win involving a dramatic underpromotion in a position previously thought to have been a draw.
An endgame tablebase is a computerized database that contains precalculated exhaustive analysis of chess endgame positions. It is typically used by a computer chess engine during play, or by a human or computer that is retrospectively analysing a game that has already been played.
The Peruvian Immortal is the name given to a chess game played by the Peruvian master Esteban Canal against an unknown amateur in a simultaneous exhibition he gave at Budapest in 1934. In just 14 moves, Canal sacrificed both his rooks and his queen, finishing with Boden's mate.
A joke chess problem is a puzzle in chess that uses humor as a primary or secondary element. Although most chess problems, like other creative forms, are appreciated for serious artistic themes, joke chess problems are enjoyed for some twist. In some cases the composer plays a trick to prevent a solver from succeeding with typical analysis. In other cases, the humor derives from an unusual final position. Unlike in ordinary chess puzzles, joke problems can involve a solution which violates the inner logic or rules of the game.
Since its premiere in 1968, the film 2001: A Space Odyssey has been analysed and interpreted by numerous people, ranging from professional movie critics to amateur writers and science fiction fans. The director of the film, Stanley Kubrick, and the writer, Arthur C. Clarke, wanted to leave the film open to philosophical and allegorical interpretation, purposely presenting the final sequences of the film without the underlying thread being apparent; a concept illustrated by the final shot of the film, which contains the image of the embryonic "Starchild". Nonetheless, in July 2018, Kubrick's interpretation of the ending scene was presented after being newly found in an early interview.
Willi Schlage was a German chess master and trainer. Active as a player during the inter-war years of the Weimar Republic and later as a trainer during the rise of the Third Reich, Schlage is remembered for a game depicted in the science fiction film 2001: A Space Odyssey, which chess writers attributed to him. He is also known for an endgame position attributed to a game played with Carl Ahues, frequently presented as an example in endgame literature.
The following outline is provided as an overview of and topical guide to chess:
