“Slack space occurs on a hard drive or floppy when a file gets
partially overwritten after deletion. The new file does not
completely fill in the space created by the old file’s data. So, a
slack space of residual data remains in the area between the end of
file (EOF) boundary of the new file and the end of the cluster. On
a given disk, then, large amounts of “hidden data” exist. These
fragments may offer considerable evidence about what was deleted
from the disk….”
“Cryptography is a vast subject, and it can be as abstract as
quantum physics. The average computer sleuth, though, does not have
to know the inner workings of designing cryptographic algorithms.
But, he or she does need to know the difference between simple and
complex cryptography….”