Backward pawn

In chess, a backward pawn is a pawn that is behind the pawns of the same color on the adjacent files and that cannot be advanced without loss of material, usually the backward pawn itself. In the diagrammed position, the Black pawn on the c6 square is backward. Backward pawns are usually a positional disadvantage, since they are hard to defend. Also, the opponent can place a piece on the hole in front of the pawn without any risk of a pawn driving it away. If the backward pawn is on a half-open file, as in this case, the disadvantage is much larger, as it can be more easily attacked by an opponent's rook or queen. Pieces can become weak when they are devoted to protecting a backward pawn.
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