Making a backup copy of a disk is the least loved but most important job
you can do.  With planning, it need not be an onerous task.

There are basically three ways of making a backup of a floppy or fixed disk;
the DOS commands COPY, DISKCOPY and BACKUP (see the help files of the same
name for details about each command).  My favorite method is using the COPY
command because it is easy to copy only the files currently being used
(operations that are easy and fast encourage use).  Entire directories can be
copied quickly, and entire disks including all subdirectories can be copied
using a batch file (see the help file BATCH for more details).  Fixed disks can
be backed up to a set of diskettes, each one containing a logical grouping of
files (DOS on one, all correspondence on another, etc.).  I can backup all the
files I've modified during the day in the time it takes to return a phone call.

The other commands each have the following problems:

DISKCOPY - The copy made is an exact sector by sector copy of the original.
           This is somewhat risky because the bad sector map of the copy maps
           the bad sectors of the original disk, not the bad sectors on the
           copy, so information may be lost.  If only a few files on the disk
           have been modified, copying the individual files with COPY is
           probably faster.  If many files have been changed, use DISKCOPY to
           ensure that all changes are backed up.
BACKUP - The backup must be restored into the same directory it was read from
         so the recovery can get somewhat messy.  BACKUPs take longer and
         require more babysitting (unless done by directory in which case they
         are comparable to the COPY command so why not use the command you are
         most familiar with).

All manufacturers diskettes received should be write protected, and backed up
when received and the original stored in a safe place in case you need it
again.  Use the copy you made to run with.  If the manufacturer's diskette is
copy protected, do what the manufacturer suggests.

I'm now going to describe how I maintain backups of all my diskettes.  It
will appear that I use a great number of diskettes for this purpose and it's
true.  As Murphy would say "a diskette or drive will fail at the worst possible
time, and in the process will take as many backup copies as possible with it".
Feel free to decrease the number of copies maintained if you like, but the
philosophy of a backup copy should remain the same.  Always try to have two or
more up to date copies of a diskette.

I keep two backups of each diskette.  One backup is used on days with even
dates the other is used on odd dates.  If I'm using the computer all day, I
will backup at least twice during the day (before lunch and quitting time, or
after I've completed something I'd like to save).  If the same program or
document is being entered all the time, a simple COPY file command is all that
is required to be completely backed up!  The two backups are maintained in
case of a disk drive failure or power failure.  With three copies floating
around there is less likelihood that all three diskettes could be corrupted
at once (two diskettes in the drives and the power shuts down damaging both
original and backup for example).  With this scheme I've always got a backup
less than two days old.

I also keep a full set of backups at another location (another building). This
is especially important for businesses since insurance will not normally cover
the cost of re-development of software or re-entry of documents.  It is
a good insurance policy against fire, theft, etc..  One day (about once a
month) the archive copies are brought in and updated with the current disk
contents then taken away again that night.  Archives that never change can be
omitted from this periodic updating once the original archive is done.  This
provides a "snapshot" of all the disks and a basis for recovery should the
unthinkable happen.

If you have diskettes that are updated every day, there is an even better way
of backing up (I'll describe a scheme for businesses that can be adapted by
anyone).  Label four diskettes with the days of the week, Monday through
Thursday, and label two other diskettes Friday-A and Friday-B.  At the start or
the end of each day copy your working diskette to the day's diskette.  On
Friday, alternate between the A and B diskettes and take the copy to the other
location on the way home.  Pick up the other Friday diskette and bring it back
to the office on Monday.  No more than one day's work can be lost due to a
diskette failure and no more than a week's work lost due to a disaster such as
an office fire or theft.

MORE SUGGESTIONS ***
* If you suspect that one of your disk drives is going bad, either don't use
  the drive until it is checked, or if it must be used start a new set of
  temporary backups so the information stored up till then on the regular
  backups cannot be corrupted.

* Fixed disks are not generally repairable devices and are more commonly
  replaced with a new drive.  For this reason it is especially important that
  you keep your fixed disk completely backed up.

* When recovering a corrupted file, the time and date stamp displayed by the
  DIR command is the easiest method of determining which backup copy of the
  file is most recent.  Always set the time and date when the computer is
  started.

* The help file BADDISK has suggestions about how to recover a disk that has
  gone bad.
