Chess annotation symbols

When annotating chess games, commentators frequently use widely recognized annotation symbols. Question marks and exclamation points that denote a move as bad or good are ubiquitous in chess literature. Some publications intended for an international audience, such as the Chess Informant have a wide range of additional symbols that transcend language barriers.

The common symbols for evaluating the merits of a move are "??", "?", "?!", "!?", "!", and "!!". In these cases, the corresponding symbol is juxtaposed in the text immediately after the move (e.g. Re7? or Kh1!?, see algebraic chess notation).

Use of these annotation symbols is subjective, as different annotators use the same symbols differently. Moreover, an annotator's use of symbols is often influenced by the player's strength: a positional misjudgment that an annotator might give a "??" if played by a strong grandmaster might pass unremarked if played by a beginner.

Annotators' use of punctuation also may possibly be influenced by the result of the game regardless of the actual quality of the move; this tendency is sometimes referred to as "annotation by result".

Move symbols in increasing effectiveness of the move:

The double question mark "??" indicates a blunder, a very bad mistake. Typical moves which receive double question marks are those that overlook a tactic that wins substantial material or overlook a checkmate. A "??"-worthy move usually results in an immediately lost position. Occasionally, the sign is used for a move which transforms a won position into a draw, perhaps because the annotator feels that the mistake is unworthy of the player's skill level. They occur at all levels of play to all human competitors, but only the most basic computer programs commit such obvious mistakes.

A single question mark "?" after a move indicates that the annotator thinks that the move is a poor one that should not be played. These often lead to loss of tempo or material. The nature of the mistake may be more strategic than tactical; in some cases, the move receiving a question mark may be one that is difficult to find a refutation for. A move that overlooks a forthcoming brilliant combination from the opponent would rarely receive more than one question mark, for example.

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