Fork (chess)

In chess, a fork is a tactic in which a piece Template:Chessgloss 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 Template:Chessgloss, such as when the king is put in check. A fork is a type of Template:Chessgloss. Template:AN chess

Terminology

A fork is an example of a Template:Chessgloss. 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.<ref>{{#invoke:citation/CS1|citation |CitationClass=web }}</ref> 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.<ref>{{#invoke:citation/CS1|citation |CitationClass=web }}</ref>

A fork of the king and queen, the highest Template:Chessgloss-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.<ref name="polgar">Template:Cite book</ref><ref>Template:Cite book</ref>

Strategy

While any piece can deliver a fork, knights are particularly effective as the forking piece because they cannot be captured by the non-knight pieces they attack, and as a Template:Chessgloss they are less valuable than rooks and queens.<ref>{{#invoke:citation/CS1|citation |CitationClass=web }}</ref><ref>Template:Harvp</ref>

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

Game examples

Template:Chess diagram
This example is from the first round of the FIDE World Chess Championship 2004 between Mohamed Tissir and Alexey Dreev.<ref>{{#invoke:citation/CS1|citation |CitationClass=web }}</ref> After

Template:Pad33... 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.

Template:Chess diagram
This example is from the ninth round of the Clarin GP Final between Guillermo Soppe and Fernando Braga.<ref>{{#invoke:citation/CS1|citation |CitationClass=web }}</ref> After

Template:Pad40... Qh1+

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

Template:Col-begin Template:Col-break Template:Chess diagram small Template:Col-break Template:Chess diagram small Template:Col-end 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... Nxe4Template:Chesspunc

due to the fork trick

5. Nxe4 d5

regaining either the bishop or the knight.