I know these things about storage devices:
- They're separated into two parts: the file table and the file data
- The way these work is dictated by the file system
- All file systems have a file table and file data
- The file table can be changed without changing the file data, and vice versa
- A file can be removed from the file table for a quick delete without actually removing the file's data
So, my question is: when you change the file system on (or "format") a drive, why must all the file data be lost? Can't a computer simply remember the file table and re-create it in the format of the new system?
I'm sure you'd run into some issues with a completely full drive if the new file system requires a larger table than the old system, but other than that, I don't see why this can't be done.
I also know that after a "quick format" (where just the file table is replaced, but the new one is empty) that all the file data is still there and can be recovered with forensic tools.