Knight (chess)

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Knight in the standard Staunton pattern

The knight ( ) is a piece in the game of chess, representing a knight (armored cavalry). 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 each corner.


Movement[edit]

a b c d e f g h
8
Chessboard480.svg
b8 black knight
g8 black knight
b1 white knight
g1 white knight
8
7 7
6 6
5 5
4 4
3 3
2 2
1 1
a b c d e f g h
Location of the knights at the start of the game: b1 and g1 for White; b8 and g8 for Black
a b c d e f g h
8
Chessboard480.svg
c6 black circle
e6 black circle
b5 black circle
f5 black circle
d4 black knight
b3 black circle
f3 black circle
g3 white circle
c2 black circle
e2 black circle
f2 white circle
h1 white knight
8
7 7
6 6
5 5
4 4
3 3
2 2
1 1
a b c d e f g h
The black knight may move to any of eight squares (black dots). The white knight in this case is limited to two squares (white dots).
Chess pieces
Chess kdt45.svgChess klt45.svg King
Chess qdt45.svgChess qlt45.svg Queen
Chess rdt45.svgChess rlt45.svg Rook
Chess bdt45.svgChess blt45.svg Bishop
Chess ndt45.svgChess nlt45.svg Knight
Chess pdt45.svgChess plt45.svg Pawn

The knight move is unusual among chess pieces. When it moves, it can move to a square that is 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 pieces (of either color) to its destination square.[1] It captures an enemy piece by replacing it on its square. The knight's ability to 'jump over' other pieces means it tends to be at its most powerful in closed positions, in contrast to that of a bishop. The move is one of the longest-surviving moves in chess, having remained unchanged since before the seventh century. Because of this it also appears in most chess-related regional games. The knight moves alternately to light and dark squares.

A knight should always be close to where the action is, meaning it is best used on areas of the board where the opponent's pieces are clustered or close together. 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 three or four squares (depending on its exact location) and a knight in the corner only two. Moreover, it takes more moves for an uncentralized knight to switch operation to the opposite side of the board than an uncentralized 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 to reflect this principle.

a b c d e f g h
8
Chessboard480.svg
a8 black rook
e8 black king
c7 white knight
8
7 7
6 6
5 5
4 4
3 3
2 2
1 1
a b c d e f g h
The knight forks the king and rook.

The knight is the only piece that can move at the beginning of the game without first moving a pawn. For the reasons above, the best square for the initial move of each knight is usually one towards the center. Knights are usually brought into play slightly sooner than the bishops and much sooner than the rooks and the queen.

Because of its move pattern, the knight is especially well-suited for executing a fork.

a b c d e f g h
8
Chessboard480.svg
a8 four
b8 three
c8 two
d8 three
e8 two
f8 three
g8 two
h8 three
a7 three
b7 two
c7 three
d7 four
e7 one
f7 two
g7 one
h7 four
a6 four
b6 three
c6 two
d6 one
e6 two
f6 three
g6 two
h6 one
a5 three
b5 two
c5 three
d5 two
e5 three
f5 white knight
g5 three
h5 two
a4 four
b4 three
c4 two
d4 one
e4 two
f4 three
g4 two
h4 one
a3 three
b3 two
c3 three
d3 four
e3 one
f3 two
g3 one
h3 four
a2 four
b2 three
c2 two
d2 three
e2 two
f2 three
g2 two
h2 three
a1 three
b1 four
c1 three
d1 two
e1 three
f1 two
g1 three
h1 two
8
7 7
6 6
5 5
4 4
3 3
2 2
1 1
a b c d e f g h
Distance from the f5-square, counted in knight moves

In the numbered diagram, the numbers represent how many moves it takes for a knight to reach each square on the chessboard from its location on the f5-square.

Value[edit]

A knight is approximately equal in strength and value to a bishop. The bishop has longer range, but is restricted to only half the squares on the board. Since the knight can jump over pieces which obstruct other pieces, it is usually more valuable when the board is more crowded (closed positions). A knight is best when it has a 'support point' or outpost – a relatively sheltered square where it can be positioned to exert its strength remotely.[2] 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 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.[3]

Properties[edit]

a b c d e f g h
8
Chessboard480.svg
a8 black rook
d8 black rook
g8 black king
a7 black pawn
b7 black pawn
f7 black pawn
g7 black bishop
h7 black pawn
d6 black pawn
g6 black pawn
d5 white knight
e5 black pawn
e4 white pawn
h4 black queen
a3 white pawn
f3 white pawn
b2 white pawn
d2 white queen
g2 white pawn
h2 white pawn
b1 white king
d1 white rook
h1 white rook
8
7 7
6 6
5 5
4 4
3 3
2 2
1 1
a b c d e f g h
A powerful knight occupying a hole (d5) in the enemy pawn structure.

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.

Whereas two bishops cover each other's weaknesses, two knights tend not to cooperate with each other as efficiently. As such, a pair of bishops is usually considered better than a pair of knights (Flear 2007:135). World Champion José Raúl Capablanca considered that a queen and a knight is usually a better combination than a queen and a bishop. However, Glenn Flear found no game of Capablanca's that supported his statement and statistics do not support the statement either (Flear 2007:135). In an endgame without other pieces or pawns, two knights generally have a better chance against a queen than two bishops or a bishop and a knight would (see fortress (chess)).

From Mednis
a b c d e f g h
8
Chessboard480.svg
a8 white king
c8 black king
a7 white pawn
e2 white knight
8
7 7
6 6
5 5
4 4
3 3
2 2
1 1
a b c d e f g h
White to move cannot win. White wins if Black is to move.

Compared to a bishop, a knight is often not as good in an endgame. The knight's potential range of movement is more limited, which often makes it less suitable in endgames with pawns on both sides of the board. However, this limitation is less important in endgames with pawns on only one side of the board. Knights are superior to bishops in an endgame if all the pawns are on one side of the board. Furthermore, knights have the advantage of being able to control squares of either color, unlike a lone bishop. Nonetheless, a disadvantage of the knight (compared to the other pieces) is that by itself it cannot lose a move to put the opponent in zugzwang (see triangulation and tempo), while a bishop can. 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 (Mednis 1993:7–8).

a b c d e f g h
8
Chessboard480.svg
c4 white bishop
g2 white king
c1 black knight
h1 black knight
8
7 7
6 6
5 5
4 4
3 3
2 2
1 1
a b c d e f g h
Knight trapped by an enemy bishop, knight trapped by a king

At the end of the game, if one side has only a king and a knight while the other side has only a 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 in general about equal in value. Paradoxically, checkmate with two knights sometimes can be forced if the weaker side has a single extra pawn, but this is 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.

Notation[edit]

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 (and in some variants of fairy chess N is used for the popular fairy chess piece, the nightrider).

Unicode[edit]

Unicode defines two codepoints for knight:

U+2658 White Chess Knight (HTML ♘)

U+265E Black Chess Knight (HTML ♞)

See also[edit]

Notes[edit]

  1. ^ Because of this, the move can also be described other ways, such as one square diagonally and one square orthogonally 'outward' (not ending adjacent to its starting square), or one square orthogonally followed by one square diagonally outward. The latter describes the move of the horse in xiangqi, which cannot jump.
  2. ^ Glossary
  3. ^ Jeremy Silman, The Art of Planning, Chess Life, August 1990

References[edit]