Karen Coghlan wrote:

> I have been learning how to formatt my hard drive and am curious.
> What is the difference between deleteing the del tree and
> reformatting the hard drive.

Karen,

Let me give you a little background first.  A storage disk (floppy,
hard, zip, etc) is a
circular piece of magnetic material (very similar to a cassette tape or
video tape).
Information is stored on the disk in concentric (each one smaller in
diameter than the
previous) rings.  The rings are called TRACKS.

Every TRACK is divided into storage containers called SECTORS.  Every
sector
is the same size on a given disk.  When your Operating System (O/S)
stores information
into the SECTORS, it does so  in a semi-random fashion.  To keep track
of where it
has placed the information, the O/S uses a File Allocation Table (FAT)
which is sort
of like a Table of Contents (or an index) for a book.

When you issue the FORMAT command, all the old data is erased, and the
recording
marks which identify the beginning and end of each sector are rewritten
along with a
fresh, empty FAT.  It is just like a brand new disk.

When you use the DEL or DELTREE commands, you are instructing the O/S to

"not display the file(s) in any directory listing"  and to make the
sectors available for
storage of other information  (I know the first part of that sounds
awkward, but I
didn't  want to use the concept of "hiding the file"  because you might
confuse that
with something called the HIDDEN ATTRIBUTE for a file)

DELETE (and it's variations) **do not remove files**.  They are still
listed
in the FAT and the data still exists on the disk but the FAT is fooled
into thinking
that those SECTORS are now free to be used for other storage items.  So
the
data may remain readable for months or for only a few minutes (remember
the
storage system works in a random manner).

DOS version 5 (and earlier versions) had a program called UNdelete which
could
"restore" those hidden files.  Since Windows 9x has a recycle bin, MS
(in their infinite
wisdom) decided to stop including the UNdelete program.  If you still
have a copy
of an older DOS, then the UNDELTE program will still work, but you must
use it
from a true DOS prompt not from a DOS window.

--
Jim Meagher
=====
Micro Solutions Consulting        Member of The HTML Writers Guild
http://www.ezy.net/~microsol     International Webmasters Association
410-543-8996                MS Site Builder Network - Level 2 member
=====

         The PCBUILD web site always needs good submissions.  If
          you would like to contribute to the website, send any
               hardware tech tips or hardware reviews to:
                           [log in to unmask]