In short, if one of the two hard drives inside the My Book Mirror Edition ever fails the second drive still has a copy of all your files. The 'Mirror' part of the name indicates that this dual-drive storage system automatically mirrors (duplicates) your valuable data using RAID 1 mirroring technology for extra protection. This attractive dual hard drive external storage solution is offered in either a 1TB (two 500GB HDDs) or 2TB (two 1TB HDDs) capacities … but that’s not what makes this drive so special.
