Chess strategy
From Wikipedia, the free encyclopedia
- This article uses algebraic notation to describe chess moves.
Chess strategy is concerned with the evaluation of chess positions and setting up goals and long-term tactics for future play. During the evaluation, a player must take into account the value of the pieces on the board, pawn structure, king safety, position of pieces, and control of key squares and groups of squares (e.g. diagonals, open files, black or white squares), and the possible moves the opponent will make after any move made.
The most basic way to evaluate one's position is to count the total value of pieces on both sides. The point values used for this purpose are based on experience. Usually pawns are considered to be worth one point, knights and bishops three points each, rooks five points, and queens nine points. The fighting value of the king in the endgame is approximately four points. These basic values are modified by other factors such as the position of the piece (e.g. advanced pawns are usually more valuable than those on their starting squares), coordination between pieces (e.g. a bishop pair usually coordinates better than the a bishop plus a knight), and the type of position (knights are generally better in closed positions with many pawns, while bishops are more powerful in open positions).
Another important factor in the evaluation of chess positions is the pawn structure or pawn skeleton. Since pawns are the most immobile 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, such as the possibility to develop an attack.
Contents |
[edit] Values of the pieces
Material advantage applies both strategically and tactically. Generally more pieces or an aggregate of more powerful pieces means greater chances of winning. A fundamental strategic and tactical rule is to capture opponent pieces while preserving one's own.
Bishops and knights are called minor pieces. A knight is about as valuable as a bishop, but less valuable than a rook. Rooks and the queen are called major pieces. Bishops are usually considered slightly better than knights in open positions, such as toward the end of the game when many of the pieces have been captured, whereas knights have an advantage in closed positions. Having two bishops is a particularly powerful weapon, especially if the opposing player lacks one or both of his bishops.
Three pawns are more likely to be useful than a knight in the endgame, but in the middlegame a knight is often more powerful. Two minor pieces are stronger than a single rook, and two rooks are slightly stronger than a queen.
One commonly used simple scoring system is:
-
Piece Value Pawn 1 Bishop 3 Knight 3 Rook 5 Queen 9
Under a system like this, giving up a knight or bishop in order to win a rook ("winning the exchange") is advantageous and is worth about two pawns. This of course ignores such complications as the current position and freedom of the pieces involved, but it is a good starting point. In an open position, bishops will be more valuable than knights (a bishop pair can easily be worth seven points or more in some situations); conversely, in a closed position, bishops will be less valuable than knights. The king is priceless since its loss causes the loss of the game.
[edit] Space
All other things being equal, the side which controls more space on the board has an advantage. More space means more options, which can be exploited both tactically and strategically. If all of one's pieces are developed and no tactical tricks or promising long-term plan is apparent, he could try to find a move which will enlarge his influence, particularly in the center. However, in some openings, one player will accept less space for a period of time to set up a counterattack in the middlegame. This is one of the concepts behind hypermodern play.
[edit] Defending pieces
It is important to defend one's pieces even if they are not directly threatened. This helps stop possible future campaigns from the opponent. This approach has an antecedent in the theory of Aron Nimzowitsch who referred to it as "overprotection." Similarly, if one spots undefended enemy pieces, one should take advantage of those pieces' weakness.
[edit] Exchanging pieces
To exchange pieces means to capture a hostile piece and then allow a piece of the same value to be captured. As a general rule of thumb, exchanging pieces eases the task of the defender who typically has less room to operate in.
Exchanging pieces is usually desirable to a player with an existing advantage in material, since it brings the endgame closer and thereby leaves the opponent with less time in which to recover ground. In the endgame even a single pawn advantage may decide the game.
When playing against stronger players, many beginners attempt to constantly exchange pieces "to simplify matters". However, stronger players are often relatively stronger in the endgame, whereas errors are more common during the more complicated middlegame.
Note that "the exchange" may also specifically mean a rook for a bishop or knight.
[edit] Specific pieces
[edit] Pawns
In the endgame, passed pawns, those which cannot be hindered by enemy pawns from promotion, are strong, especially if they are advanced or protected by another pawn. A passed pawn on the sixth row is roughly as strong as a knight or bishop and will often decide the game. (Also see isolated pawn, doubled pawns, backward pawn, connected pawns).
[edit] Knights
Since knights can easily be chased away with pawn moves, it is often advantageous for knights to be placed in "holes" in the enemy position (an outpost), squares where they cannot be attacked by a pawn. Such a knight on the fifth rank is a strong asset, and one on the sixth rank may exercise as much power as a rook. A knight at the edge or corner of the board controls fewer squares than one on the board's interior.
[edit] Bishops
A bishop always stays on squares of the color it started on, so once one of them is gone, the squares of the other color become more difficult to control. When this happens, pawns moved to squares of the other color do not block the bishop, and enemy pawns directly facing them are stuck on the vulnerable color.
A fianchettoed bishop at, e.g., g2 after pawn g2-g3, can provide a strong defense for the castled king on g1 and often exert pressure on the long diagonal h1-a8. After a fianchetto, giving up the bishop can weaken the holes in the pawn chain; doing so in front of the castled king may thus impact its safety.
In general, a bishop is of roughly equal value to a knight. In certain circumstances, one can be more powerful than the other. If the game is "closed" with lots of interlocked pawn formations, the knight tends to be stronger, because it can hop over the pawns while the bishop is blocked by them. A bishop is also weak if it is restricted by his own pawns, which are blocked and on the bishop's color.
In an open game with action on both sides of the board, the bishop tends to be stronger because of its long range. This is especially true in the endgame; if passed pawns race on opposite sides of the board, the player with the bishop usually has better winning chances than the player with the knight.
[edit] Rooks
Rooks have more scope of movement on Half-open files (ones which do not contain pawns of one's own colour). Rooks on the seventh rank can be very powerful as they attack pawns which can only be defended by other pieces, and they can restrict the enemy king to its back rank. A pair of rooks on the player's seventh rank is often a sign of a winning position.
In middlegames and endgames with a passed pawn, Tarrasch's rule states that rooks, both friend and foe of the pawn, are usually strongest behind the pawn rather than in front of it.
[edit] Queen
Queens are the most powerful pieces. They have great mobility and can make many threats at once. For these reasons, mating attacks involving the queen are easier to achieve than those without. It is generally wise to wait to develop the queen until after the knights and bishops have been developed to prevent the queen from being attacked by minor pieces and losing tempos.
[edit] King
During the middle game, the king is often best protected in a corner behind his pawns. If the rooks and queen leave the first rank however, an enemy rook can checkmate the king by invading the first rank. Moving one of the pawns in front of the king (making a luft) can allow it an escape square, but may weaken the king's position.
The king can become a strong piece in the endgame. With reduced material, a quick mate is not an immediate concern anymore, and moving the king towards the center of the board gives it more opportunities to make threats and actively influence play.
[edit] Quotes
- "Strategy requires thought; tactics requires observation." - Max Euwe
- "When you see a good move wait - look for a better one." - Emanuel Lasker
[edit] See also
[edit] References
This article does not cite any references or sources. (April 2008) Please help improve this article by adding citations to reliable sources. Unverifiable material may be challenged and removed. |
[edit] Further reading
- John Nunn (2001). Understanding Chess Move by Move. Gambit. An International Grandmaster explains the thinking behind every single move of many world-class games.
- Jeremy Silman (1999). The Amateur's Mind: Turning Chess Misconceptions into Chess Mastery. Siles Press. A chess teacher analyzes and corrects the thinking of advanced beginners.
- James Eade (2001). Chess for Dummies. Gambit. A comprehensive guide for beginners.
- Yasser Seirawan (2005). Winning Chess Strategies. Everyman Chess. ISBN 1-85744-385-3.
[edit] External links
- 64 Commandments of Chess by Bruce Pandolfini
- Chess Strategy, Second Edition (also at Gutenberg-project), and Chess and Checkers: the Way to Mastership by Edward Lasker
- The Blue Book of Chess; "Teaching the Rudiments of the Game, and Giving an Analysis of All the Recognized Openings" by Howard Staunton
- Chess Strategy, free lessons on basic elements.
|