Why do hares hop?

They hop to get places, and because their build and the power in their back feet doesn't allow them to walk like humans or other animals.

If you'd like me to describe a hop to you, I can, but it's really what it sounds like; the rabbit pushes off the ground with his hind feet, goes into the air an inch or two, and puts his front legs down before his back legs. A hop covers maybe half a foot to a foot of ground, depending on how fast your rabbit is going, how strong he is, what breed he is, and where he is.