Data remanence

Data remanence is the residual physical representation of information that was
saved and then erased in some fashion. This remanence may be enough to enable the
data to be reconstructed and restored to a readable form. This can pose a security threat
to a company that thinks it has properly erased confidential data from its media. If the
media is reassigned (object reuse), then an unauthorized individual could gain access to
your sensitive data.

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