Pins

How to spot it

A pin is an attack on a piece that cannot move without exposing a more valuable piece behind it. When the piece behind is the king, the pin is absolute: the pinned piece may not legally leave the line. When it is the queen or a rook, the pin is relative: the piece can move, but something bigger falls.

To spot a pin, look for two enemy pieces on the same file, rank or diagonal with the more valuable one behind. A king and queen on an open file or a long diagonal are the classic targets. Then ask whether one of your bishops, rooks or your queen can step onto that line.

Exploit the pin. A pinned piece cannot run away, so attack it again, ideally with a pawn. A pinned piece also does not really defend anything, so whatever it seems to guard may be free.

Check a pin before you trust it. A relative pin can be broken when moving the pinned piece creates an even bigger threat.

Puzzles

Ten puzzles, rated 700 to 1700. A wrong move shows the engine’s refutation, and a missed puzzle comes back for review.