A block is a defensive tactic in

chess Chess is a board game for two players, called White and Black, each controlling an army of chess pieces in their color, with the objective to checkmate the opponent's king. It is sometimes called international chess or Western chess to disti ...

in response to an attack, consisting of interposing a

piece Piece or Pieces (not to be confused with peace) may refer to: Arts, entertainment, and media Games * Piece (chess), pieces deployed on a chessboard for playing the game of chess * ''Pieces'' (video game), a 1994 puzzle game for the Super NES * P ...

between the opponent's attacking piece and the piece being attacked. This type of blocking will only work if the attacking piece is a type that can move linearly an indefinite number of squares such as a

queen Queen or QUEEN may refer to: Monarchy * Queen regnant, a female monarch of a Kingdom ** List of queens regnant * Queen consort, the wife of a reigning king * Queen dowager, the widow of a king * Queen mother, a queen dowager who is the mother ...

rook Rook (''Corvus frugilegus'') is a bird of the corvid family. Rook or rooks may also refer to: Games *Rook (chess), a piece in chess *Rook (card game), a trick-taking card game Military * Sukhoi Su-25 or Rook, a close air support aircraft * USS ...

, or

bishop A bishop is an ordained clergy member who is entrusted with a position of authority and oversight in a religious institution. In Christianity, bishops are normally responsible for the governance of dioceses. The role or office of bishop is ca ...

and there is at least one empty square in the line between the attacking and attacked piece. Blocking is not an option when the attacking piece is directly adjacent to the piece it is attacking, or when the attacking piece is a

knight A knight is a person granted an honorary title of knighthood by a head of state (including the Pope) or representative for service to the monarch, the church or the country, especially in a military capacity. Knighthood finds origins in the Gr ...

(because knights "jump over other pieces" and cannot be blocked). When an opponent's attack on a piece is blocked, the blocking piece is to some extent pinned, either relatively or absolutely, until a future move by either side allows it to be unpinned. A

check Check or cheque, may refer to: Places * Check, Virginia Arts, entertainment, and media * ''Check'' (film), a 2021 Indian Telugu-language film * ''The Checks'' (episode), a 1996 TV episode of ''Seinfeld'' Games and sports * Check (chess), a thr ...

on a

king King is the title given to a male monarch in a variety of contexts. The female equivalent is queen, which title is also given to the consort of a king. *In the context of prehistory, antiquity and contemporary indigenous peoples, the tit ...

by an opponent's queen, rook, or bishop can sometimes be blocked by moving a piece to a square in line in between the opponent's checking piece and the checked king. The blocking piece is then absolutely pinned to the king by the attacking piece. Another type of interposing in chess can involve placing a piece between two opponent's pieces where one of those pieces is protecting the other, or they are both protecting each other. This

chess tactic In chess, a tactic is a sequence of moves that each makes one or more immediate threats ─ that is, a check, a material threat, a checkmating sequence threat, or the threat of another tactic ─ which culminates in the opponent being unable to r ...

can be called ''

interference Interference is the act of interfering, invading, or poaching. Interference may also refer to: Communications * Interference (communication), anything which alters, modifies, or disrupts a message * Adjacent-channel interference, caused by extr ...

''.

Blocking and initiative

When the attack cannot be ignored, the attacking player has the

initiative In political science, an initiative (also known as a popular initiative or citizens' initiative) is a means by which a petition signed by a certain number of registered voters can force a government to choose either to enact a law or hold a pu ...

. The defending player may be able to acquire the initiative by blocking and attacking at the same time, by attacking an undefended attacker with the blocking piece, with a

discovered attack In chess, a discovered attack is a direct attack revealed when one piece moves out of the way of another. Discovered attacks can be extremely powerful, as the piece moved can make a threat independently of the piece it reveals. Like many chess t ...

, or when the block is also a check or a

cross-check In chess, a cross-check is a tactic in which a check is played in response to a check, especially when the original check is blocked by a piece that itself either delivers check or reveals a discovered check from another piece. Sometimes the term ...

References

Chess tactics Chess terminology {{chess-stub

Blocking and initiative

See also

References