Knight (chess)

The knight (unicode|♘ unicode|♞, sometimes referred to by players as a 'horse') is a piece in the game of chess, representing a knight (armoured cavalry). It is normally represented by a horse's head.

Each player starts with two knights, which start on the rank closest to the player. Expressed in algebraic notation, the white knights start on b1 and g1, while the black knights start on b8 and g8.

Movement

chess diagram|=
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Location of the knights at the start of the game.|chess diagram|=
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=8 |__|__|__|__|__|__|__|__|=7 |__|__|__|__|__|__|__|__|=6 |__|__|xo|__|xo|__|__|__|=5 |__|xo|__|__|__|xo|__|__|=4 |__|__|__|nd|__|__|__|__|=3 |__|xo|__|__|__|xo|__|__|=2 |__|__|xo|__|xo|__|__|__|=1 |__|__|__|__|__|__|__|__|=
This knight may move to any of eight different squares.|The knight move is unusual among chess pieces. When it moves, it can move two squares horizontally and one square vertically, or two squares vertically and one square horizontally. The complete move therefore looks like the letter 'L'. Unlike all other standard chess pieces, the knight can 'jump over' all other pawns and pieces (of either colour) to its destination square. It captures an enemy piece by moving into its square.

The move is one of the longest surviving moves in chess, having remained unchanged since before the seventh century AD. Because of this it also appears in most chess-related national games. The knight moves alternately to white and black squares.

Pieces are generally more powerful if placed near the center of the board, but this is particularly true for a knight. A knight on the edge of the board attacks only four squares and a knight in the corner only two. Moreover, it takes more moves for a decentralized knight to switch operation to the opposite side of the board than a decentralized bishop, rook, or queen. The mnemonic phrases "A knight on the rim is grim" or "A knight on the rim is dim" are often used in chess instruction and reflect these features.

The knight is the only piece that can move at the beginning of the game before any pawn move has been made. Because of the above reasons, in most situations the best square for the initial move of each knight is one towards the center. Knights are usually brought into play slightly sooner than the bishops and much sooner than the rooks and the queen.

The knight is the only piece that can be in position to attack a king, queen, bishop, or rook without being reciprocally attacked by that piece. The knight is thus especially well-suited for executing a fork.

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= 8 |x4|x3|x2|x3|x2|x3|x2|x3|= 7 |x3|x2|x3|x4|x1|x2|x1|x4|= 6 |x4|x3|x2|x1|x2|x3|x2|x1|= 5 |x3|x2|x3|x2|x3|nl|x3|x2|= 4 |x4|x3|x2|x1|x2|x3|x2|x1|= 3 |x3|x2|x3|x4|x1|x2|x1|x4|= 2 |x4|x3|x2|x3|x2|x3|x2|x3|= 1 |x3|x4|x3|x2|x3|x2|x3|x2|= a b c d e f g h
Distance from the f5 square, as counted in knight moves.In the diagram at right, the numbers represent how many moves it takes for a knight to reach each square on the chess board from its location on the f5 square. Observing and even memorizing the patterns (diagonally 2-4-2-4-2-4, horizontally and vertically 3-2-3-2-3-2) helps making quick decisions in chess such as knowing where to move other pieces not to be in the direct 'fire' of the knight or even maneuvering the knight itself better.

Value

chess diagram|=
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=8 |rd|__|__|rd|__|__|kd|__|=7 |pd|pd|__|__|__|pd|bd|pd|=6 |__|__|__|pd|__|__|pd|__|=5 |__|__|__|nl|pd|__|__|__|=4 |__|__|__|__|pl|__|__|qd|=3 |pl|__|__|__|__|pl|__|__|=2 |__|pl|__|ql|__|__|pl|pl|=1 |__|kl|__|rl|__|__|__|rl|=
A powerful knight occupying a hole (d5) in the enemy pawn structure.|A knight is approximately equal in strength and value to a bishop. The bishop's range is larger, but it is restricted to only half the squares on the board. Since the knight is capable of jumping over obstructing pieces, it is considered to be more valuable when the board is more crowded (closed positions). A knight is best when it has a 'support point'—a square that acts as relatively sheltered place for it to stop at and exert its strength remotely. [http://www.jeremysilman.com/chess_glossary/glossary_chess_terms_s.html#supportpoint Glossary] On the fourth rank a knight is comparable in power to a bishop, and on the fifth it is often superior to the bishop, and on the sixth rank it can be a decisive advantage. This is assuming that the knight is taking part in the action; a knight on the sixth rank which is not doing anything useful is not a well-placed piece. [Jeremy Silman, "The Art of Planning", Chess Life, August 1990] (See chess piece point value.)

Enemy pawns are very effective at harassing knights because a pawn attacking a knight is not itself attacked by the knight. For this reason, a knight is most effective when placed in a weakness in the opponent's pawn structure, i.e. a square which cannot be attacked by enemy pawns. In the diagram at right, White's knight on d5 is very powerful—more powerful than Black's bishop on g7.

In endgames with pawns on both sides of the board, a knight is often not as good as a bishop as its range is limited. With pawns in only one side of the board, knights have the advantage of being able to attack pawns standing at either color. In either case, a disadvantage of the knight is that by itself it cannot lose a move (see triangulation and tempo), while a bishop can.

Whereas two bishops cover each other's weaknesses, two knights in general do not cooperate efficiently. However, a queen and a knight is often a better combination than a queen and a bishop. Also, in an endgame without other pieces, two knights have a better chance against a queen than two bishops or a bishop and a knight against the queen (see fortress (chess)).

chess diagram|=
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=8 |__|__|__|__|__|__|__|__|=7 |__|__|__|__|__|__|__|__|=6 |__|__|__|__|bd|__|__|nl|=5 |__|__|__|__|__|__|__|__|=4 |__|__|__|bl|__|__|__|__|=3 |__|__|__|__|__|__|__|__|=2 |__|__|__|__|__|__|__|__|=1 |__|__|__|nd|__|__|__|__|=
Two trapped knights trapped by two enemy bishops|At the end of the game, if one side has only a king and a knight while the other side has only king, the game is a draw since a checkmate is impossible. When a bare king faces a king and two knights, checkmate can occur only if the opponent commits a blunder by moving his king to a square where it may be checkmated on the next move. Otherwise, a checkmate can never be forced. However checkmate can be forced with a bishop and knight, or with two bishops, even though the bishop and knight are conceptually held to be of equal value. Paradoxically, checkmate with two knights sometimes can be forced if the weaker side has a single extra pawn, but this is essentially a curiosity of little practical value (see two knights endgame). Pawnless endings are a rarity, and if the stronger side has even a single pawn, an extra knight should give him an easy win. A bishop can trap (although it cannot then capture) a knight on the rim (diagram), especially in the endgame.

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From Mednis
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kl| |kd| | | | | |=
pl| | | | | | | |=
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White to move cannot win. White wins if Black is to move.Unlike the other pieces, a knight cannot "lose a move" to put the opponent in zugzwang. In this position, if the knight is on a white square and it is White's turn to move, White cannot win. Similarly, if the knight was on a black square and it was Black's turn to move, White cannot win. In the other two cases, White would win. If instead of the knight, White had a bishop on either color of square, White would win with either side to move harvcol|Mednis|1993|pp=7–8.

Notation

In algebraic notation, the usual modern way of recording chess games, the letter "N" stands for the knight ("K" is reserved for the king); in descriptive chess notation, "Kt" is sometimes used instead, mainly in older literature. In chess problems and endgame studies, the letter "S", standing for the German name for the piece, "Springer", is often used, "N" instead being used for the popular fairy chess piece, the nightrider.

ee also

* Chess piece
* Knight's tour
* Knight's tour graph
* Staunton chess set
* Chess piece point value
* Bishop and knight checkmate
* Two knights endgame

Notes

References

*citation
author=Brace, Edward R.
year=1977
title=An Illustrated Dictionary of Chess
publisher=Hamlyn Publishing Group|isbn=1-55521-394-4
pages=155

*citation
author=Barden, Leonard
year=1980
title=Play better Chess with Leonard Barden
publisher=Octopus Books Limited
isbn=0-7064-0967-1
pages=10,11

*citation
last = Mednis| first = Edmar | authorlink = Edmar Mednis
title = Practical Knight Endings
publisher = Chess Enterprises
year = 1993
id = ISBN 0-945470-35-5