This lesson introduces one of the most important tactic building blocks in chess: the pin. A pin is a move which forces one of the opponent’s pieces to stay put because moving it would be illegal (an absolute pin) or exposes a more valuable piece behind it (a relative pin).

In the diagram below two pins can be recognized. The black Knight at c6 is pinned to the King and it is illegal to move this piece. The white Knight at f3 is pinned to the Queen and makes it very unlikely that it will be moved, but White still has the choice to move it.



Only Bishops, Rooks and Queens are able to pin an opposing pieces down. Kings, Knights, and pawns cannot pin other pieces down. Any piece can be pinned down except the king.
A pin that often occurs in openings is the move Bb5 and the diagram above is in fact an example of such an opening.

A pin is very useful in a lot of tactical combinations. Since the pinned piece cannot move out of the line of attack it is rather easy to attack the pinned piece. Furthermore a piece that is unable to move is rather useless as a defender or an attacker.

The difference between a relative pin and an absolute pin may be very important. The most famous example of a pin that didn’t work can be found in the game De Legal vs Saint Brie as played in 1750 in Paris.

It is called Legal’s Mate.

The game can be automatically replayed (if Javascript enabled) by pressing the button with the black circle below the chessboard.

This is a very nice game, because it also shows that you may loose a game by winning the Queen.

There is some discussion about the original Legal-Brie game. Weinstein in his book “Combinations and traps in the opening” mentions this game with Nc6 and after Nxe5 says “…but Legal can be pardoned, he was 80 years old when he played this”

At this moment we have learned a lot of chess lessons, but you may have a feeling that you want to learn more openings. Please wait with this. Try to focus on strategics and tactics and on some of the endgames, but in order to survive the opening we will learn some rules for the opening in the next lesson.