Bootable Archives are created by adding a special bootable section when the user is backing up the data to CD/DVDs. The user is able to restore the data from these archives without having to run the program, but by simply booting from these CD/DVDs.
All CD/DVDs created with the program are bootable. But after booting from an incorrect CD/DVD you will be asked to insert the main CD/DVD. As for a partition archive is concerned the main CD/DVD is always the first one, but dealing with an HDD archive the main CD/DVD is the last one. During the restore process you will be asked to insert the necessary CD/DVD.