As the name implies, the edge sander gets in those hard-to-reach areas that the drum sander and vibrating or large orbital sander can't reach.
Unlike the drum or vibrating sander, the edge sander is hand-held. It does have a dust bag, though, and does have an orbital motion.
The edge sander is not the Black & Decker you might have in your garage. It's heavy, expensive, and has the kind of power you need to sand down hardwood floor. Please don't think of using your own orbital sander, as this will only lead to frustration. The edge sander is relatively inexpensive to rent and will make your work go faster.

