There is a little bit of marketing spin around this area. Many of these drives reviewed here proudly state they are formatted for Mac, and they are, but all that really does is save you a little time and effort. With a little (and we mean little), know how you can format any external drive to work on any system. You can even format them so they work on both simultaneously. So this ‘feature’ is purely one of convenience. Vice versa, you can also take one of the pre-Mac formatted drives and easily format it to work on your PC. Don’t believe the hype people.