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Fork (chess) - Wikipedia

  • ️Fri Apr 09 2021

From Wikipedia, the free encyclopedia

abcdefgh
8

a8 black rook

d7 black king

b6 white knight

g4 black pawn

f3 white rook

h3 white rook

c1 white king

8
77
66
55
44
33
22
11
abcdefgh

The white knight forks Black's king and rook. Black's pawn forks the white rooks.

In chess, a fork is a tactic in which a piece attacks multiple enemy pieces simultaneously. The attacker usually aims to capture one of the forked pieces. The defender often cannot counter every threat. A fork is most effective when it is forcing, such as when the king is put in check. A fork is a type of double attack.

A fork is an example of a double attack. The type of fork is named after the type of forking piece. For example, a fork by a knight is a knight fork. The attacked pieces are forked.[1] If the king is one of the attacked pieces, the term absolute fork is sometimes used, while a fork not involving the enemy king is a relative fork.[2]

A fork of the king and queen, the highest material-gaining fork possible, is sometimes called a royal fork. A fork of the enemy king, queen, and one (or both) rooks is sometimes called a grand fork. A knight fork of the enemy king, queen, and possibly other pieces is sometimes called a family fork or family check.[3][4]

While any piece can deliver a fork, knights are particularly effective at creating forks because they cannot be captured by the pieces they attack, and as a minor piece they are less valuable than rooks and queens.[5][6]

Compared to forks by other pieces, a queen fork requires more specific conditions to be helpful due to the queen's higher value. However, a queen fork can often lead to material or positional gain when the forked pieces are undefended, poorly coordinated, or when one piece is the king.[citation needed]

Tissir vs. Dreev, 2004

abcdefgh
8

a8 black rook

g8 black king

b7 black pawn

d7 black queen

f7 black pawn

g7 black bishop

h7 black pawn

g6 black pawn

c5 white pawn

d5 black pawn

a4 black pawn

e4 black knight

f4 white queen

a3 white pawn

f3 white pawn

a2 white bishop

d2 white bishop

g2 white pawn

h2 white pawn

c1 white rook

h1 white king

8
77
66
55
44
33
22
11
abcdefgh

Position after 33.Qe5–f4

This example is from the first round of the FIDE World Chess Championship 2004 between Mohamed Tissir and Alexey Dreev.[7] After

 33... Nf2+ 34. Kg1 Nd3

White resigned. In the final position the black knight forks White's queen and rook; after the queen moves away, Black will win the exchange.

Soppe vs. Braga, 1998

abcdefgh
8

g8 black king

f7 black pawn

g7 black bishop

e6 black pawn

h6 black pawn

b5 black pawn

d5 black knight

e5 white knight

e4 black queen

g4 white pawn

b3 white pawn

h3 white pawn

f2 white pawn

c1 white bishop

d1 white queen

f1 white king

8
77
66
55
44
33
22
11
abcdefgh

Position after 40.Nxe5

This example is from the ninth round of the Clarin GP Final between Guillermo Soppe and Fernando Braga.[8] After

 40... Qh1+

White resigned. The only move is 41.Ke2 which enables a royal fork with 41...Nc3+, winning the queen.

abcdefgh
8

a8 black rook

c8 black bishop

d8 black queen

e8 black king

f8 black bishop

h8 black rook

a7 black pawn

b7 black pawn

c7 black pawn

d7 black pawn

f7 black pawn

g7 black pawn

h7 black pawn

c6 black knight

f6 black knight

e5 black pawn

c4 white bishop

e4 white pawn

c3 white knight

f3 white knight

a2 white pawn

b2 white pawn

c2 white pawn

d2 white pawn

f2 white pawn

g2 white pawn

h2 white pawn

a1 white rook

c1 white bishop

d1 white queen

e1 white king

h1 white rook

8
77
66
55
44
33
22
11
abcdefgh

Position after 4.Nc3. Black can play 4...Nxe4 since he has a fork trick.

abcdefgh
8

a8 black rook

c8 black bishop

d8 black queen

e8 black king

f8 black bishop

h8 black rook

a7 black pawn

b7 black pawn

c7 black pawn

f7 black pawn

g7 black pawn

h7 black pawn

c6 black knight

d5 black pawn

e5 black pawn

c4 white bishop

e4 white knight

f3 white knight

a2 white pawn

b2 white pawn

c2 white pawn

d2 white pawn

f2 white pawn

g2 white pawn

h2 white pawn

a1 white rook

c1 white bishop

d1 white queen

e1 white king

h1 white rook

8
77
66
55
44
33
22
11
abcdefgh

After 4...Nxe4 5.Nxe4 d5, White is forked and Black will regain a piece.

In the Two Knights Defense (1.e4 e5 2.Nf3 Nc6 3.Bc4 Nf6) after 4.Nc3, Black can eliminate White's e4-pawn immediately with

4... Nxe4!

due to the fork trick

5. Nxe4 d5

regaining either the bishop or the knight.

  1. ^ "The Fork • lichess.org". lichess.org. Retrieved 2021-04-09.
  2. ^ "Chess Game Strategies - Next Chess Move". Chess Game Strategies.
  3. ^ Polgar, S.; Truong, P. (2015). A World Champion's Guide to Chess: Step-by-Step Instructions for Winning Chess the Polgar Way!. Russell Enterprises, Incorporated. p. cxix. ISBN 978-1-941270-33-2. Retrieved 2024-11-12. Here White can give a "family fork" by attacking three black pieces at once: king, queen, and rook, with 1.Nf4+.
  4. ^ Hooper, David; Whyld, Kenneth (1996) [1992]. The Oxford Companion to Chess (2nd ed.). Oxford University Press. p. 132 at family check. ISBN 0-19-280049-3.
  5. ^ "Fork in Chess - Chess Terms". Chess.com. Retrieved 2021-04-09.
  6. ^ Hooper & Whyld (1996), p. 143, fork
  7. ^ "Tissir vs. Dreev, Tripoli 2004". Chessgames.com.
  8. ^ "Guillermo Soppe vs. Fernando Braga, (1998)". Chessgames.com.