I fully understand the diffference between cloning and creating an image. Our small trading firm has decided that cloning each of our existing hard drives to external usb drives would best suit our needs. We would also like to take advantage of using a separate partition on the usb drives to create images of each hard drive and then use the incremental or differential backups as further precautions. I have a couple of questions. First, the drives we are backing up are fairly large but do not contain that much data. How much unallocated space will be left on the usb drive after cloning. Ideally we would like a lot of space remaining to then partition the drive for further image backup as I previously mentioned. Or should I not even bother partitioning the hard drive and simply create folders with the backup images I am going to create? Would that create problems if I want to boot from the usb drive(which my BIOS supports)? Thanks for any help.