Some humans, in an effort to be like a car,like to wear roller skates or they stand on a skateboard. Both items have wheels like a car. I suppose the humans can't get to where they are going fast enough. I thought a dog would not be in such a hurry, but I was wrong. Some dogs do like to get where they are going faster than paws alone. This dog will stick with my four paws. I am sharing a link that shows a skating dog.