File History is a backup application that continuously protects your personal files stored in Libraries, Desktop, Favorites, and Contacts folders. It periodically (by default every hour) scans the file system for changes and copies changed files to another location. Every time any of your personal files has changed, its copy will be stored on a dedicated, external storage device selected by you. Over time, File History builds a complete history of changes made to any personal file.
Read More – http://blogs.msdn.com/b/b8/archive/2012/07/10/protecting-user-files-with-file-history.aspx
