[lazee barok]

actually, sandpaper actually had bits of a material tougher than sand. just that the first ones were called sandpaper. I think it may have been grains of diamond? or is that nail files?
the use of sandpaper is to get rid of roughness on wood, or level things out, or even to put patterns on wood. they mean that by smooth sandpaper that sandpaper with the stuff on it, but it's all smooth, so it wouldn't do any of that stuff.