The Pawn is the only chess piece which does not move backwards.
The Pawn moves forward along files only.
On its first move a Pawn may move only one (1) or two (2) squares forward along the file on which it starts. If a Pawn has already moved, it may only move forward one (1) square.
In diagrams 1 & 2 below, the yellow arrows show where each Pawn can move to.

Diagram 1
The next diagram shows all the moves which each pawn could make.

Diagram 2
The Pawn is unique, not only because it does not move backwards or sideways (only forward), but because it is the only piece which does not capture in the same way that it moves.
A Pawn captures by moving only one square diagonally forward to a file next to it.
- diagonally forward to the right
- diagonally forward to the left
In diagram 3 below, all the moves the white Pawns can make are shown by the yellow arrows and the all the captures by the BLUE arrows.
Note how the white Pawn on “g5” cannot move forward and has nothing to capture.

Diagram 3
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