When you are using a Raid setup on your computer, you need to use 2 or more hard drives. For example if you have 3 hard drives, and you install a program on one of them, it is installed over all 3 hard drives. This is the Raid system. The beauty of it is, if one of your hard drive gets corrupted, then there is enough data on the other 2 drives to automatically rebuild the missing part, so you don't have to worry about restoring your computer so much.
