To hop is to bounce or jump, either on one foot or both feet. Bunnies hop. People hop. And, sometimes, people do a dance called the "Bunny Hop." No joke.
If you lose a shoe in a rainstorm, you might hop along on one foot until you find it again. You can also hop into and out of things, or up to or down from a height: "Hop in the car, let's go!" Something that's "a hop, skip, and a jump" from where you are is extremely close, a short trip. The Old English root of hop is hoppian, "to spring, leap, or dance."