Hanging piece
A hanging piece is a piece that is attacked by the opponent and has no defender, so it can be captured for free unless its owner moves it, defends it or makes a bigger threat.
Also called: undefended piece
A piece hangs when two things are true at once: an enemy unit attacks it, and none of your own units guards the square it stands on. Capturing it costs the other side nothing, which is why a hanging piece is the cheapest kind of material gain on the board.
Most hanging pieces appear through oversights rather than clever play. A knight is developed to a square nobody covers, a defender is traded off, or a move uncovers an attack the player did not see. Before every move, ask which of your pieces are undefended and which of the opponent's pieces can reach them. Do the same for the other side: a quick scan of the opponent's pieces for anything unprotected often turns up a free capture.
The opposite habit is just as useful. When you move, check whether the move leaves something behind. Moving a defender away is the classic way to hang a piece without noticing.
Do not treat a defended piece as safe in every case. A piece guarded once can still be lost if it is attacked by something worth less, since the exchange costs the defender more than it wins. Hanging means undefended, but the practical question is always whether the capture nets material. Counting attackers against defenders on the square settles it.
A neighboring idea is Poisoned pawn. A poisoned pawn is a pawn that can be captured, but whose capture lets the opponent punish the greedy player with a tactic that costs more than the pawn is worth.
Compare it with Double attack. A double attack is one move that creates two threats at once, whether they come from a single piece or from two, and whether they aim at pieces or at checkmate.
A neighboring idea is Relative pin. A relative pin is a pin in which the piece behind the pinned piece is more valuable but is not the king, so the pinned piece may legally move but would lose that piece.
Knowing "Hanging piece" helps most once you can spot it in a real game. A first lesson with George Li starts from your own games and finds the tactics you keep missing.
Related terms
A loose piece is a piece that no friendly piece or pawn protects, which makes it a target even when nothing attacks it yet and gives the opponent a chance for a double attack.
A tactic is a short, forcing sequence of moves that exploits a concrete feature of the position, such as a fork, pin or unprotected piece, to win material, deliver mate or reach a clear gain.
A double attack is one move that creates two threats at once, whether they come from a single piece or from two, and whether they aim at pieces or at checkmate.
A blunder check is a quick test, made by a person before moving or by software afterward, that looks for a move which hangs material, allows a tactic or loses the game outright.
Removing the defender means getting rid of the one piece that protects a target, by capturing it or forcing it to move, after which the target can be taken for free.
Guides that go further
What to decide first, the questions to ask, what a first lesson should show and the red flags to avoid.
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A game review, a read on your level and a written study plan from George Li.
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