It is quite easy to confuse the random-orbit sander with a regular orbital sander: Not only do the two names sound alike, but the tools also share a common design, with compact housings and rounded palm-grip tops.

There is one small but very important distinction between the two tools: An orbital sander has a square sanding pad, and a random-orbit sander has a round pad.

This is the one thing that makes all the difference. The round pad on a this type of sander moves in “random orbits,” meaning it vibrates in tiny circles, and it also spins in circles. As a result, this single compact tool can be used for both stock removal and ultra-smooth sanding. And because the pad vibrates and spins simultaneously, it all but eliminates swirl that ordinary orbital sanders often leave behind.

While a random-orbit sander won’t remove wood as quickly as a belt sander, and it’s slightly more difficult to control than an orbital finishing sander, but the random-orbit sander is probably the more versatile portable electric sander.