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The Why and How of Chess ... The En passant pawn capture
Every pawn, on its first move, has the choice of moving either one or two squares forward.
Look at this diagram.
Black may think, "If I move my pawn one square White will capture it so I'll move it two squares," and the position would be as shown in the diagram below:
However, White can still capture the black pawn as if it had moved only one square.
The new position would be as shown in the diagram below. White removes the black pawn from the board and places the white pawn on the square the black pawn would have moved to if it had only moved one square forward.
This special way of capturing is called capturing en passant and is abbreviated e.p. En passant is a French expression which means "in passing." The en passant capture must be done immediately after the black pawn advances two squares. If White plays another move, he cannot then decide to capture en passant!
Frequently Asked Questions
What is en passant in chess?
En passant is a special pawn capture that can occur immediately after a pawn moves two squares forward from its starting position and an opposing pawn could have captured it if it had moved only one square.
When can you capture en passant?
You can capture en passant only on the very next move after your opponent moves their pawn two squares forward.
Is en passant mandatory?
No, capturing en passant is optional. You may choose not to capture.
Why is en passant important?
En passant prevents pawns from bypassing enemy pawns and gaining an unfair positional advantage.