Interference (chess) Interference (chess) In the game of chess, interference occurs when the line between an attacked piece and its defender is interrupted by sacrificially interposing a piece. It is a chess tactic which seldom arises, and is therefore often overlooked. Opportunities for interference are rare because the defended object must be more valuable than the sacrificed piece, and the interposition must itself represent a threat. In the position at left, White to play will apparently be obliged to retreat the knight from f5, because the squares to which it could advance are all guarded. However, the interference move 1.Nd6+ interrupts the
Pin (chess) h2 pins the pawn to the 2nd rank. With mate being inevitable, White resigned after move 26. Bibliography Pin (chess) In chess, a pin is a situation brought on by an attacking piece in which a defending piece cannot move without exposing a more valuable defending piece on its other side to capture by the attacking piece. Moving the attacking piece to bring on the pin is called pinning; the defending piece so restricted is described as pinned. Only pieces that can move an indefinite number of squares in a horizontal, vertical, or diagonal line (i.e. bishops, rooks, and queens)