This article describes "How To" back up a site using JoomlaPack.
The current version and one that works is 1.1.0 of JoomlaPack
More current versions are not used because there were so many problems getting it to work correctly.
The back up zip file will be stored on your PC. It is imperative that your PC is also backed up for redundancy. A service like Carbonite will ensure that your back ups are backed up.