The pawns only move straight forward, one square at a time,
except at their first move, when they have the option of moving
two squares. In contrast to the pieces, the pawns do not capture
in the way they move. They move straight forward, but they
capture diagonally to the right and left, again only one square,
and only forward. Therefore a pawn can only capture such pieces
or pawns as occupy squares of the same colour as the square on
which it stands. If, in moving two squares, a pawn traverses a
square on which it could have been captured by a hostile pawn,
that pawn has the right to capture it, as if it had moved only
one square. This is called capturing EN PASSANT. However, this
capture can only be effected on the very next move, otherwise the
privilege of capturing en passant is lost.

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8 | | | | | | | | |
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7 | | | | | | | | |
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6 | | | | * | | * | | |
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5 | | | * | | | | * | |
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4 | | | | | ^Kt| | | |
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3 | | | * | | | | * | |
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2 | | | | * | | * | | |
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1 | | | | | | | | |