Pawn chain

A pawn chain consists of same-colored pawns placed diagonally on neighboring files. A file is a vertical line of the board. Because pawns capture one square diagonally forward, each pawn farther back relative to the direction of movement protects the next pawn. A chain may contain only two pawns or extend across several files.

The rearmost pawn is the base. It is the only member not defended by another pawn in the chain, so it is often a logical target. The most advanced pawn is the head and gains space, but its security depends on support from behind. Attacking the base can weaken the whole formation, although the opponent's pieces may still defend it.

Effects on the position

• The chain controls squares of one color and can restrict enemy pieces.
• A bishop that moves on the same square color occupied by the chain may be blocked by its own pawns.
• A pawn break, an advance or capture that challenges the formation, against the base or a middle link can change the structure and open lines.
• The chain's direction often suggests where more space exists, meaning more squares are available for maneuvering, but choosing a plan, a set of actions serving a goal, also depends on the pieces and kings.

Every chain consists of connected pawns, but not all connected pawns form a chain. Two pawns on adjacent files and the same rank make a pawn duo, not a chain until one advances into a square protected by the other.