In chess

Chess

Chess is a two-player board game played on a chessboard, a square-checkered board with 64 squares arranged in an eight-by-eight grid. It is one of the world's most popular games, played by millions of people worldwide at home, in clubs, online, by correspondence, and in tournaments.Each player...

, a tactic refers to a sequence of moves which limits the opponent's options and may result in tangible gain. Tactics are usually contrasted with strategy, in which advantages take longer to be realized, and the opponent is less constrained in responding.

The fundamental building blocks of tactics are move sequences in which the opponent is unable to respond to all threats, so the first player realizes an advantage. This includes forks

Fork (chess)

In chess, a fork is a tactic that uses a single piece to attack multiple pieces at the same time. The attacker usually hopes to gain material by capturing one of the opponent's pieces. The defender often finds himself in a difficult position in which he cannot counter all threats. The attacking...

, skewers

Skewer (chess)

In chess, a skewer is an attack upon two pieces in a line and is similar to a pin. In fact, a skewer is sometimes described as a "reverse pin"; the difference is that in a skewer, the more valuable piece is in front of the piece of lesser or equal value...

, batteries

Battery (chess)

A battery in chess is a formation that consists of two or more pieces on the same rank, file, or diagonal. It is a tactic involved in planning a series of captures to remove the protection of the opponent's king, or to simply gain in the exchanges...

, discovered attack

Discovered attack

In chess, a discovered attack is an attack revealed when one piece moves out of the way of another. Discovered attacks can be extremely powerful, as the piece moved can make a threat independently of the piece it reveals. Like many chess tactics, they succeed because the opponent is unable to meet...

s, undermining

Undermining (chess)

Undermining is a chess tactic in which a defensive piece is captured, leaving one of the opponent's pieces undefended or underdefended. The opponent has the unpalatable choice between recapturing or saving the underdefended piece...

, overloading

Overloading (chess)

Overloading is a chess tactic in which a defensive piece is given an additional defensive assignment which it cannot complete without abandoning its original defensive assignment.-Example:...

, deflection

Deflection (chess)

Deflection in chess is a tactic that forces an opposing piece to leave the square, rank or file it occupies, thus exposing the king or a valuable piece. It is typically used in the context of a combination or attack, where the deflected piece is critical to the defence...

, pins

Pin (chess)

In chess, a pin is a situation brought on by an attacking piece in which a defending piece cannot move without exposing a more valuable defending piece on its other side to capture by the attacking piece...

 and interference

Interference (chess)

Interference occurs when the line between an attacked piece and its defender is interrupted by sacrificially interposing a piece. It is a chess tactic which seldom arises, and is therefore often overlooked...

.

• The Encyclopedia of Chess Middlegames gives the following tactical categories: Double Attack, Pawns Breakthrough, Blockade, Decoying, Discovered Attack, Passed Pawn, X-ray Attack, Interception, Deflection, Pin, Demolition of Pawns, Overloading, Annihilation of Defense, Pursuit (perpetual attack), Intermediate Move, and Space Clearance.

Often tactics of several types are conjoined in a combination

Combination (chess)

In chess, a combination is a sequence of moves, often initiated by a sacrifice, which leaves the opponent few options and results in tangible gain. At most points in a chess game, each player has several reasonable options from which to choose, which makes it difficult to plan ahead except in...

.

Attacking and defending pieces

A piece is said to attack (or threaten) an opponent's piece if, in the next move, it could capture that piece. A piece is said to defend (or protect) a piece of the defender's color if, in case the defended piece were taken by the opponent, the defender could recapture right away. Attacking a piece usually, but not always (see sacrifice

Sacrifice (chess)

In chess, a sacrifice is a move giving up a piece in the hopes of gaining tactical or positional compensation in other forms. A sacrifice could also be a deliberate exchange of a chess piece of higher value for an opponent's piece of lower value....

), forces the opponent to respond if the attacked piece is undefended, or if the attacking piece is of lower value than the attacked one.

When attacked, one has several options:

• Capture the attacking piece.
• Move the attacked piece.
• Interpose another piece in between the two, if the attacker is not a knight.
• Guard the attacked piece and permit an exchange
  Exchange (chess)
  In the tactics and strategy in the board game of chess, an exchange or trade of chess pieces is series of closely related moves, typically sequential, in which the two players capture each others pieces. Any types of pieces except the kings may possibly be exchanged, i. e. captured in an...
  
  .
• Pin the attacking piece so the capture becomes illegal or unprofitable.
• Use a zwischenzug (create a counter-threat).

Gaining material

When one player is able to capture an opponent's piece or pieces without losing any of his own, that player is said to have gained material, that is, he will have more pieces on the board. The goal and threat of each basic tactic is to win material. At the professional level, it's often merely the threat of material loss that causes one player or the other to fall into a strategically worse position. In amateur games however, tactics are often overlooked by one player, and so the execution of tactics for material gain is the most common way to achieve a decisive advantage. Material gain can be accomplished by several different types of tactics.

Discovered attack

A discovered attack is a move which allows an attack by another piece. A piece is moved away so as to allow the attack of a friendly bishop, rook or queen on an enemy piece. If the attacked piece is the king, the situation is referred to as a discovered check. Discovered attacks are powerful as the moving piece may be able to pose a second threat.

A special case of a discovered check is a double check, where the piece being unmasked and the piece being moved attack the enemy king. A double check requires that the opponent moves his/her king as the king is under attack from two directions and it is impossible to counter both at the same time in any other way.

Animated example of a Discovered Attack	Animated example of a Discovered Check

Fork

A fork is a move that uses one piece to attack two or more of the opponent's pieces simultaneously, hoping to achieve material advantage, since the opponent can only counter one of the two threats. Knights

Knight (chess)

The knight is a piece in the game of chess, representing a knight . It is normally represented by a horse's head and neck. Each player starts with two knights, which begin on the row closest to the player, one square from the corner...

 are often used for forks, with their unique moving and jumping ability. A common situation is a knight jumping to c2 or c7, thereby threatening both the enemy rook

Rook (chess)

A rook is a piece in the strategy board game of chess. Formerly the piece was called the castle, tower, marquess, rector, and comes...

 and the king. Such "king forks" are particularly effective, because the opponent is forced by the rules of the game to alleviate the threat to the king. The opponent cannot choose to defend the other piece, and thus cannot use a zwischenzug to complicate the situation. Pawns

Pawn (chess)

The pawn is the most numerous and weakest piece in the game of chess, historically representing infantry, or more particularly armed peasants or pikemen. Each player begins the game with eight pawns, one on each square of the rank immediately in front of the other pieces...

 can also be effective for forking. By moving a pawn forward, it may attack two pieces; one diagonally to the left and one diagonally to the right.

Queens

Queen (chess)

The queen is the most powerful piece in the game of chess, able to move any number of squares vertically, horizontally, or diagonally. Each player starts the game with one queen, placed in the middle of the first rank next to the king. With the chessboard oriented correctly, the white queen starts...

 are also excellent forking pieces, because they can move in eight different directions. However, this is only useful if both pieces are undefended, or if one is undefended and the other is the opposing king. The queen is the most valuable piece (excluding the king), so it is usually not profitable for it to capture a defended piece.

Fork attacks can be either 'Relative', which is when the attacked units are any of the Pawns, Knights, Bishops, Rooks, or Queen(s). Or, the Fork attacks can be 'Absolute', which is when one of the attacked pieces includes the King.

Animated example of a Relative Fork Attack	Animated example of an Absolute Fork Attack

Pin

A pin is a move which forces one of the opponent's pieces to stay put because moving it would expose a more valuable piece behind it. Sometimes pinned pieces cannot move at all, as doing so would expose the king. Only bishops, rooks, and queens can pin other pieces, because they can move more than one square in a straight line.

Pin attacks can be either 'Relative' or 'Absolute', as shown by the two animated images, below. The Absolute Pin is where the more valuable piece behind is the King (this is the distinguishing feature between Absolute and Relative Pins).

Animated example of a Relative Pin Attack	Animated example of an Absolute Pin Attack

Skewer

A skewer is a move which attacks two pieces in a line, similar to a pin, except that the enemy piece of greater value is in front of the piece of lesser value. After the more valuable piece moves away, the lesser piece can be captured. Queens, rooks, and bishops can perform the skewer.
Skewer attacks can be either 'Relative' or 'Absolute', as shown by the two animated images, below. The Absolute Skewer is where the more valuable piece in front is the King (this is the distinguishing feature between Absolute and Relative Skewers).

With Absolute Skewers, because it's the King that's attacked, the King is in Check and, unless the attacker can be dealt with (by capture, or by blocking the Check with a Pawn or another Piece), the attacked King will have to step aside, allowing the attacking unit to capture the less valuable Pawn or Piece behind.

If the attacked unit wasn't the King - say, a Rook - then it would be a Relative Skewer and should the situation require it, the Rook 'could' remain in place, at risk of being captured, for the sake of protecting whatever unit is behind.

Animated example of a Relative Skewer Attack	Animated example of an Absolute Skewer Attack

Pawns

Pawns are extremely useful in the game and are far more powerful than meets the eye. For instance, since pawns are the least valuable chess piece, they can be used to capture defended pieces. A single pawn approaching will force a more powerful piece, such as a rook or a knight, to retreat. A simple move of a pawn may reveal a hidden threat (see Discovered attacks). Also, when pawns are arranged in a diagonal line, with the frontmost pawns guarded by the pawns behind, they form an almost impenetrable wall capable of protecting any pieces directly behind them. Furthermore, a pawn which has progressed all the way to the opposite side of the board may be promoted

Promotion (chess)

Promotion is a chess rule describing the transformation of a pawn that reaches its eighth rank into the player's choice of a queen, knight, rook, or bishop of the same color . The new piece replaces the pawn on the same square and is part of the move. Promotion is not limited to pieces that have...

 to any other piece except a king. However, a weak pawn structure can be a big weakness.

Sacrifices

Sacrificing some material is often necessary to throw the opponent's position out of balance. The sacrificed material is sometimes able to be regained with interest a couple of moves later. Pawn sacrifices in the opening are known as gambit

Gambit

A gambit is a chess opening in which a player, most often White, sacrifices material, usually a pawn, with the hope of achieving a resulting advantageous position. Some well-known examples are the King's Gambit , Queen's Gambit , and Evans Gambit...

s; they are usually not intended for a short-term gain, but instead to achieve a more active position.

Direct attacks against the enemy king

King (chess)

In chess, the king is the most important piece. The object of the game is to trap the opponent's king so that its escape is not possible . If a player's king is threatened with capture, it is said to be in check, and the player must remove the threat of capture on the next move. If this cannot be...

 are often started by sacrifices. A common example is sacrificing a bishop on h2 or h7, checking the king, who usually must take the bishop. This allows the queen and knight to develop a fulminate attack.

Zugzwang

Zugzwang (German for compulsion to move) occurs when a player is forced to make an undesirable move. The player is put at a disadvantage because he would prefer to pass and make no move, but a move has to be made, all of which weaken his position. Situations involving zugzwang occur uncommonly, but when they do occur, it is almost always in the endgame, where there are fewer choices of available moves.

Zwischenzug

Zwischenzug (German for intermediate move) is a common tactic which, instead of countering a direct threat, a move is played which poses an even more devastating threat, often an attack against the queen or the king. The opponent has to counter that threat first, and this will ideally change the situation to a disadvantage for that player.

The concept of a zwischenzug is often listed as a tactic, but might properly be called a counter-tactic instead. The effect of a zwischenzug is to change the status quo before a tactic can come to fruition. The near ubiquity of the zwischenzug makes long combinations all the more rare and impressive.

See also

• Outline of chess: Chess tactics
• Chess strategy
• Pawn structure
  Pawn structure
  In chess, the pawn structure is the configuration of pawns on the chessboard. Since pawns are the least mobile of the chess pieces, the pawn structure is relatively static and thus largely determines the strategic nature of the position.-General observations:Weaknesses in the pawn structure, such...
  
  
• Tempo (chess)
  Tempo (chess)
  In chess, tempo refers to a "turn" or single move. When a player achieves a desired result in one fewer move, he "gains a tempo" and conversely when he takes one more move than necessary he "loses a tempo"...
  
  
• Triangulation (chess)
  Triangulation (chess)
  Triangulation is a tactic used in chess to put one's opponent in zugzwang. That is, it gets to the same position with the other player to move, when it is a disadvantage for that player to move, e.g. he has to give up a blockade and let the other player penetrate his position...
  
  

External links

• Predator at the Chessboard - A Field Guide to Chess Tactics - Learn chess tactics
• Tactics technical paper suite
• ChessGYM - Tactical chess problems
• Chess Tactics Server - Tactical chess problems
• Chess Tempo - Tactical chess problems
• Chess Tactics Repository - Tactical chess problems
• Adaptive Tactics Server -- Tactical chess problems
• Practice your tactics by playing -- Get together with other players
• IdeaChess -- Tactical chess problems
• Chess Tactics Videos -- Includes video clips of 15 different Chess Tactics