On Thu, 05 Nov 2015 11:31:23 -0500, Wolf K wrote:


A hard drive stores by changing the surface properties of the disk.

Yes, you should wipe solid state memory as well. "Delete" does not in
fact erase file data, it merely changes the information about the file
so that the OS will no longer read the data. Just what's done and how
it's done depends on the OS.

I believe the probability of any normal user recovering overwritten data
is close to zero.
While one may fantasize about the challenge one's hd will be for the NSA
to read, unless you're a terrorist they are unlikely to bother with your
discarded hardware, they have better things to do.
Having said this, it is important to protect data. In my case, being
quite old, it's entirely possible my wife will be discarding my stuff and
she doesn't know about these things. I use veracrypt and aescrypt to
protect sensitive data. The rest anyone can have.