CHESS STRATEGY

'Chess strategy' is concerned with the evaluation of chess positions and with setting up goals and long-term tactics for future play. During the evaluation, a player must take into account the value of pieces on the board, pawn structure, king safety, positioning, 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 worth one point, knights and bishops three points each, rooks five points (the value difference between a rook and a bishop being known as the exchange), and queens nine points. The fighting value of the king in the endgame is equivalent to four points. These basic values are modified by other factors such as ''position of the piece'' (e.g. advanced pawns are usually more valuable than those on initial positions), ''coordination between pieces'' (e.g. a bishop pair usually coordinates better than the a bishop plus knight) or ''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

Values of the pieces

Positioning

Defending pieces

Exchanging pieces

Specific pieces

Pawns

Knights

Bishops

Rooks

Queen

King

Quotes

See also

Further reading

External links

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.
Pawns, 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 has lost 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. Two rooks are stronger than a queen, but not by much.
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 infinitely valuable since its loss causes the loss of the game.

Positioning

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.

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 Nimzowitch who referred to it as "overprotection." Similarly, if a player spots undefended pieces of the opponent, he or she should take advantage of those pieces' weakness.

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.

Specific pieces

Pawns

Main articles: Pawn (chess), Pawn structure

In the endgame, 'passed pawns', those which cannot be hindered by enemy pawns from promotion, are strong, especially if they are advanced. 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).

Knights

Main articles: knight (chess)

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, 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.

Bishops

Main articles: bishop (chess), fianchetto

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 don't block the bishop, and enemy pawns directly facing them are stuck on the vulnerable color.
A ''fianchettod'' 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 as 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 can win over the player with the knight.
An endgame in which the parties have bishops moving on different colours is almost always drawn, even if one side is two pawns ahead.

Rooks

Main articles: rook (chess)

Rooks have more scope of movement on half-open files (ones which don't 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 an endgame with a passed pawn, Tarrasch's rule states that rooks, both friend and foe of the pawn, are strongest ''behind'' the pawn rather than in front of it.

Queen

Main articles: queen (chess)

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. Because the loss of a queen usually results in the loss of the game, it is generally wise to wait to develop a queen until after the knights and bishops have been developed.

King

Main articles: king (chess)

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 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.

Quotes

★ ''"Strategy requires thought; tactics requires observation."'' - Max Euwe

★ ''"When you see a good move wait - look for a better one."'' - Emanuel Lasker

See also

★ Chess tactics

★ Chess terminology

Further reading

★ Understanding Chess Move by Move, John Nunn, , , Gambit, 2001, An International Grandmaster explains the thinking behind every single move of many world-class games.

★ The Amateur's Mind: Turning Chess Misconceptions into Chess Mastery, Jeremy Silman, , , Siles Press, 1999, A chess teacher analyzes and corrects the thinking of advanced beginners.

★ Chess for Dummies, James Eade, , , Gambit, 2001, A comprehensive guide for beginners.

★ Winning Chess Strategies, Yasser Seirawan, , , Everyman Chess, 2005, ISBN 1-85744-385-3

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.