ggoogling it
Google En Passant

google en passant and you will be blessed and enlightened by the knowledge of the chess gods
im putting this in off-topic so hopefully nobody will be mad at me
The en passant is a chess move in which a pawn captures a pawn by moving behind it after it advanced 2 squares. This was to make sure pawns cannot escape enemy pawns by advancing 2 squares. Here is en passant in action:
3.dxc6 is the en passant move. No google required.
google en passant and you will be blessed and enlightened by the knowledge of the chess gods
im putting this in off-topic so hopefully nobody will be mad at me