2
January 2001
I've been told deleting data doesn't really delete it. Is this
true?
Yes, it is true. When you delete data it isn't actually removed from
your computer. At first, the information is moved to the trash or
recycle bin. When you empty the bin or the bin clears itself, the
computer changes the name slightly so the operating system can't see
it. Over time the data will be eventually overwritten by newer information.
It isn't unknown for old data to sit on a computer for years. This
can be embarrassing or worse when throwing or giving away a computer.
A couple of years ago one
British buyer of a second hand laptop found his new computer contained
Paul Macartney's financial records. Before getting rid of an old
computer you should delete any important or personal data and make
sure it is permanently deleted.
The most simple (and least certain) way is to empty the recycle bin
and then run defrag, you can make this more effective by starting
in Safe Mode and deleting the swap
file (search for *.swp) before running defrag. This way will overwrite
most deleted data.
A more certain way is to repartition and reformat the hard drive.
Surprisingly, this alone doesn't guarantee old data is gone forever.
But once you have reinstalled your operating system and applications
then you can be reasonably sure it is all gone.
The most certain way of destroying old data is to use a "shredder"
program. This overwrites the space a number of times and makes sure
the data is unrecoverable. These programs are included as part of
utility packages or can be downloaded free from sites such as Tucows
or C-Net,
just do a search for "shredder".
Don't assume you have nothing to hide because you don't get up to
anything untoward on your computer. If you are regular computer user
you will have passwords, unsent correspondence,draft documents, financial
statements and details that could at the very least embarrass you.
When deleting data, make sure that data has been copied, backed-up
or isn't useful before permanently erasing it. Once it has gone it
is gone forever. Lost data is the only irreplaceable thing on your
computer.