Chess Lesson

1
Chess Lesson 2

• Chess Club
• University of California, San Diego
• 10/24/08

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The Pin
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The most commonly used tactic in chess

• Entire chess games have revolved around the pin
• creation
• threat of creation
• prevention

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What is a pin?

• Definition a simultaneous attack on two pieces
  on a straight line, one directly and one
  indirectly
• The less valuable piece is in front of the line,
  and attacked directly
• pinned piece
• The more valuable piece is in back of the line,
  and attacked indirectly
• shielded piece
• If the front piece were to move, the back piece
  would be exposed to attack

Shielded
Pinned
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Only pieces that move in straight lines can pin

• Rooks, queens, bishops
• Bishops are the most commonly used pinners, since
  they are worth less than the others

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Two kinds of pins

• Absolute the shielded piece is the King. The
  pinned piece cannot move, as that would expose
  the King to check. The most powerful type of pin.

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Two kinds of pins

• Relative the shielded piece is anything other
  than the King. Although pinned, the pinned piece
  can still move and attack just as any other
  piece, only at the cost of losing the shielded
  piece.

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Why is the pin so powerful?

• Pressure one piece restrains two
• Restraint on opponents game, reducing his
  possibilites
• The threat to pile up on the pinned piece
• Attack the pinned piece with a worthless unit,
  such as a pawn

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Example of piling up
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Two common pins in practice

• Bishop to g5, pinning knight on f6 to queen

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Two common pins, cont.

• Rook to e1 after castling, pinning piece on
  e-file to enemy King

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What to do if you are stuck in a pin?

• Attack the piece causing the pin

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What to do if you are stuck in a pin?

• Block the line of attack with another unit

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What to do if you are stuck in a pin?

• Move the pinning piece out of harms way and
  counterattack with a greater threat, such as a
  check (only works with relative pins)

Nxe5! Bxd1 Nxf7 K moves
Kxd1