I know on a linux harddrive their filesystems ext 2,3,4, and others...etc support a place on one of their superblocks (or somewhere on the HDD)
. Which linux uses to write the uuid when installing for the first time, i.e that you retrieve from sudo blkid for that HDD. This is persistent meaning it is stored on the harddrive and can be used to uniquely identify a linux harddrive/partition.

I recently boot with a live linux cd on my windows 7 computer and issued the sudo blkid which gave me the uuid for the windows 7 os. Then I rebooted and sudo blkid again and to much my wonder I got the same uuid for the microsoft machine/harddrive/partitions.

This makes me think microsoft stores the uuid on the harddrive (persistently and in away that blkid knows how to access it)

I am curious where this value is stored on a microsoft ntfs harddrive.
And How universal is this ( i.e does an old microsoft or DOS based system have a uuid stored somewhere on the fat 12 , 16, 32 ,...etc harddrive?

This is import to me because I am wondering if I can use it to write simple disk imaging software that people can use with out haveing to wonder what drive or partitions to back up. I know norton ghost is a great product but can be sometimes hard to understand what label corresponds to what harddrive.

Basically it would be nice if it where true that every os out their wrote a uuid to the harddrive then I could be almost 99.99999999999% sure that this would be a unique way of know what harddrive to backup... even if it was a removable media that gets mounted/different label everytime it is used

Does anybody know for sure
Thanks for help