Simply put, a mirror Image backup adds an extra layer of protection by creating a copy or "mirror image" of your computer by backing it up to an external hard drive that you provide. Your Mirror Image backup includes your entire computer. (Not just the files and folders, but also your operating system and software programs, such as Microsoft Word). If your computer crashes and you need to get up and running again quickly, you can use your Mirror Image backup to restore your entire computer...  operating system and all to the way it was before the crash. We told you it was easy!