Some people say they're nothing but rats with bushy tails, but I really don't get it because they're really cute little critters. To watch in the wild anyway, I don't think they'd make good pets.
And chipmunks are especially cute, but I don't see them as often as the little reddish brown ones. When I was a kid we spent the summer at a campground where they all over the place. I think it was because a lot of campers were feeding them even though you're not supposed to do that, but it was so fun watching them. One time I was outside eating a Crunchy chocolate bar and a chunk of it fell on the ground, and then a squirrel ran down from a tree, picked it up and started munching away. You'd they'd prefer a chocolate bar with nuts in it.