Knight (chess)


The knight is a piece in the game of chess and is represented by a horse's head and neck. Each player starts with two knights, which are located between the rooks and bishops.

History

The knight, along with the king and the rook, has the oldest defined movement of any chess piece, its movement being unchanged since the invention of chaturanga in India around the 6th century. Similar pieces are found in almost all games of the chess family. The ma of xiangqi and janggi are slightly more restricted; conceptually, the piece is considered to pass through the adjacent orthogonal square, which must be unoccupied, rather than "jumping". Another related piece is the keima of shogi, which moves like a knight but may only move two squares forward followed by one square sideways, restricting its movement to two possible squares.

Names

The knight is colloquially sometimes referred to as a "horse", which is also the translation of the piece's name in several languages. Some languages refer to it as the "jumper", reflecting the knight's ability to move over pieces in its path: Polish skoczek, Danish/Norwegian springer, Swedish springare, German Springer, Luxembourgish Sprénger, Slovene skakač. In Sicilian it is called sceccu, a slang term for a donkey, derived from the Arabic sheikh, who during the Islamic period rode from village to village on donkeys collecting taxes.

Movement

Compared to other chess pieces, the knight's movement is unique: it may move two squares vertically and one square horizontally, or two squares horizontally and one square vertically. While moving, the knight can jump over pieces to reach its destination. Knights capture in the same way, replacing the enemy piece on the square and removing it from the board. Knights and pawns are the only pieces that can be moved in the initial position.

Value

Knights and bishops, collectively referred to as, are considered approximately equal in value. Bishops utilize a longer range, but can only move to squares of one color. The knight's value increases in since it can jump over blockades. Knights and bishops are stronger when supported by other pieces to create outposts, and become more powerful when they advance, as long as they remain.

Properties

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, 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. 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; statistics do not support the statement, either. 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.
Compared to a bishop, a knight is often not as good in an endgame. A knight can only exert control over one part of the board at a time and often takes multiple moves to reposition to a new location, which often makes it less suitable in endgames with pawns on both sides of the board. This limitation is less important, however, 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 is that by itself it cannot lose a move to put the opponent in zugzwang, 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 were on a black square and it were 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.
In an endgame where 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, a checkmate can never be forced; checkmate can occur only if the opponent commits a blunder by moving their king to a square where it can be checkmated on the next move. Checkmate can be forced with a bishop and knight, however, 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. Pawnless endings are a rarity, and if the stronger side has even a single pawn, an extra knight should give them an easy win. A bishop can trap a knight on the rim, especially in the endgame.

Stamma's mate

In a few rare endgame positions where the opposing king is trapped in a corner in front of its own pawn, it is possible to force mate with only a king and knight in a pattern known as Stamma's mate, which has occasionally been seen in practice. In the position below, from Nogueiras–Gongora, Cuban championship 2001, Black played 75...Nxf6??, incorrectly assuming that the ending would be drawn following the capture of the last white pawn on a2.. Play continued 76.Nxf6 Ke5 77.Nd7+ Kd4 78.Kf4 Kc3 79.Ke3 Kb2 80.Kd2 Kxa2 81.Kc2 Ka1 82.Nc5 Ka2 83.Nd3 Ka1 84.Nc1 and Black resigned, as 84...a2 85.Nb3 is mate.

Notation

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

Knight variations

Even among sets of the standard Staunton pattern, the style of the pieces varies. The knights vary considerably. Here are some examples.

Unicode

defines two codepoints for knight:
♘ U+2658 White Chess Knight
♞ U+265E Black Chess Knight