ChessWorld Hitchhiker's Guide to Chess

Scope: This glossary does not intend to cover player names, opening names, or Composition terms. The Glossary aims to relate the terms to ChessWorld where possible when giving examples.
If you have contributions, corrections or questions, please post them to the Chess Forum for discussion.
There is a dedicated Chess Openings Glossary

Glossary Course Modules with Game Examples

Glossary Course Modules with Tactical Puzzle Examples

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C

Candidate move
One of a number of possible realistic moves. There may be a number of legal moves available but only moves that can achieve something positive within the framework of the current game can be called candidate moves.

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Castling
A move in which the king and a rook move simultaneously and the only move where the king is allowed to move more than one square. "Castling" is recommended to improve one's king safety and so is an important move to understand and use.

A player can either castle "kingside" or "queenside". Castling Kingside is castling their king with the rook on their right. If you are playing White, Castling kingside takes the king from e1 to g1 while the rook from h1 moves to e1. See diagram below:-

Before castling Kingside:-








Analyse position

After castling Kingside:-








Analyse position

Castling "queenside" takes the king from e1 to c1 while the rook from a1 moves to d1. See diagram below:-

Before castling queenside:-







Analyse position

After castling queenside:-







Analyse position

As can be observed from the examples above, the King is moved two squares in total to either the right or to the left. Then the Rook on that side of the board is placed by the king. If castling queenside the rook on a1 goes to d1. If castling Kingside, the rook on h1 goes to f1. "Castling" may only be carried out if the following conditions are all *TRUE* for the player who intends to "castle" their king into safety :

1) The King must not be in Check. A player cannot castle in response to a "Check" from the opponent. So for example, you cannot castle if your King was in check as shown below:-







Analyse position

White must first do something about the Check from the bishop on b4. White cannot just use the Castling move here to get out of check.

2) The King cannot have moved earlier in the game. If the King has moved, the player can no longer castle on either side of the board.

3) The Rook which is relevant for the castling has not moved previously. If the Queen's rook has moved, then "castling queenside" is no longer possible. If the King's rook has moved, then "castling kingside" is no longer possible.

4) The King is not passing through any checking squares when it moves either two squares to the left or right for the castling movement. The Final square the King moves to must not under check as well. There is a sometimes misunderstood aspect of this, which is shown below:-

In the following position, castling queenside is NOT legal because the Black queen is attacking the d1 square which is a square the White King would be passing through if it did castle queenside :-








Analyse position

However, in a slightly different position as shown below, castling queenside IS legal and okay to do:-







Analyse position

Although the Black bishop is attacking the b1 square, it does not matter. The White king is not passing through the b1 square. Korchnoi apparently in a high level World championship candidates match once asked the arbiter if castling queenside was legal. This shows that this particular subtlety has not been confidently understood by even top Grandmasters :)

When castling, the King must be moved first and not the rook, because a Rook move would constitute a legal move in itself. So therefore you must when castling on Chessworld, first click on the King, and then click on the two squares to the left or right of the king to where you intend to castle.

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Casual game
A non-tournament encounter.

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Centre
Squares d4, d5, e4 and e5 - the four squares in the very centre of the board.








Analyse position



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Check
When the king is directly attacked. The game is lost unless the king can be moved our of check, or another piece can be placed between the king and the attacking piece, or the attacking piece can be captured.








Analyse position



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Checkmate








Analyse position

If the king is in check and there is no legal move that can get him out of check (see check) he is checkmated and the game is lost.

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Chess Clock
A timing device used in tournament play, After making a move, a player depresses the button on his side of the device which stops his timer and starts that of his opponent. Beginners are often intimidated by chess clocks but one quickly adjusts to their use, without which many games could drag on for days.

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Chess Forum
A forum where anything related to Chess can be discussed. Chessworld has a very good Chess Forum

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Closed Game
A closed game arises after 1.d4 and Black plays 1...d5 in return

See also "Open game" and "Semi-open" game definitions.

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Composition
One of the most artistic aspects of chess is the composition, which is an artificial position composed by a problemist. There are many rules governing the creation of a composition, one of the most important of which is that only a single solution is allowed.

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Conditional Moves
Conditional moves are often used in correspondence chess.

On Chessworld.net they are moves you put in when you have finished your move, which anticipate the opponent's reply. For example, if you have just played Nxp and you think your opponent will play an obvious recapture, then you could create an If-then move sequence for that.

By using conditional moves, the game can be fast-forwarded past standard opening sequences of a series of obvious captures. For more information of how they work on Chessworld, refer to the FAQ.

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Connected pawns
Pawns which can protect or be protected by a pawn on an adjacent file. Connected passed pawns are considered most valuable in the endgame. In the diagram below, White has a connected pawn island on the queenside. Black by contrast has isolated pawns.








Analyse position



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Consultation Game
A game in which one or both sides are made up of two or more players in consultation. Chessworld has hosted many such Consultation games in the form of "Rest of World" games. One such game has been annotated by two times British Champion IM George Botterill. (Please swap Kingscrusher for "Rest of world").

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Control
A player controls a square by occupying or by having more pieces which can occupy it with a single move than his opponent.

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Correspondence Chess
Chess played on ChessWorld can be termed "Server based correspondence chess". More traditionally correspondence chess can be played by Email or even by traditional snail-mail. A player usually has more than one game in progress, and the time limit is most usually measured in days per move. This form of chess makes it very easy to chat and socialise between moves.

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