Why is data recoverable?

[NogginBoink]

Originally posted by: Ipno
Its absolutely fascinating what can be recovered.

Consider this, the Department of Defense's standard is to overwrite the data with random bits 7 times.

7 times! That would kindof hint at the fact that maybe after 6 times they can still get the data off ...

How do they do it? here is a fascinating read on the subject. After you read that you'll most likely decide to just demolish your used hard drive if you have anything really sensitive on there.

Schweet!

"If commercially-available SPM's are considered too expensive, it is possible to build a reasonably capable SPM for about US$1400, using a PC as a controller [6]."

A homebrew scanning probe microscope!

BTW, that's a fascinating read, and not terribly intimidating to non-academics.

 

[f95toli]

Why do they use a SEM to recover data from a HD? (SEM=scanning electron microscope)
The data on the HD is stored magentically and SEMs can usually not see the magnetic domains (it might be possible, but it is definitly not a standard method). Why not use a SPM instead?