A B C D E F G-H I-L M-N O P Q-R S T U-Z

Elo Rating: A mathematical system, now used worldwide, devised by Prof. Arpad Elo to rank chess players.

En Passant: A French term that literally means “in passing.” When a pawn advances two squares (something it can only do if it has not yet moved) and passes an enemy pawn on an adjacent file that has advanced to its fifth rank, it may be captured by that enemy pawn as if the advancing pawn had moved only one square. This optional capture may be made only on the first opportunity, else the right in that instance is permanently lost.

If Black plays 1…c7-c5 (in the diagram) White, if he wishes, may capture the pawn as if it had moved to c6. Thus, 2.dxc6. If after 1…c7-c5 White declines to capture and instead plays 2.c4, then after 2…e7-e5 White could no longer capture the c5-pawn. However, he could capture the e5-pawn by dxe6 if he so desired. In chess notation an En Passant capture is labeled by the letter e.p.

En Prise: A French term meaning “in take.” It describes a piece or pawn that is unprotected and exposed to capture. (Pronounced: on-pree).

Equality: A situation in which neither side has an advantage over the opponent.

Exchange: To trade pieces of equal worth. See Point Count. Trading a piece for something of lesser value is called a blunder or a sacrifice.

Exchange, The: A comparison of value between a Rook versus a Bishop or Knight. Thus, if you have won an enemy Rook for your Bishop, then you have won the Exchange.

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