A hanging pieceHanging means attacked with nobody defending it. Before you capture, look for the defender.

A piece is HANGING when it is attacked and has nobody defending it: you can take it for free. The opposite is true too, and it catches more people: capturing a DEFENDED piece is not free, it is a trade. Look at the marked squares — the black pawn on f5 is protected by the one on g6. Whoever takes on f5 gets taken back.

Your knight on d4 reaches two black things: the rook on b5 and the pawn on f5. Take the one that is hanging.

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