The knight moves 2 squares in one direction and 1 square
to the side. This means 2 squares up or down the board and one square to
the side OR 2squares to the left or right and then 1 square up or down
the board. The knight must go to the end of its move. It cannot go 2
squares and then stop.
Picture 1. How the knight moves. The green blobs show the squares that the knight can move to.
Picture 2. The knight is on d5. On the next move it will go to e7