There are a couple of ways to format a storage devise.
One is a full format, and this will clear all sectors and the FAT, and so it will take a while depending on how fast the storage are and of course how big it is.
A fast format on the other hand, that will just clear the FAT and so any data in the sectors are actually still there, just ready to get overwritten by something, so if you look at the devise it will say empty as that is all the cleared FAT know, but as the sectors have not been cleared the data are actually still there, clearing the FAT just take seconds.
This is why you want to be careful if you throw out / sell something with a storage device in it, that be modern electronic storage or even a old spinning hard disk, if not properly formatted your personal data could still be there and so retrieved.
When i put in the new PNY memory card today, the A229 just popped up with a MSG saying press the OK button to format it, and so i did. And 15 seconds later i was up and running.
