IBM 5150 Manual To Operations page 97

An Important Exercise:
Backing Up Your DOS Diskette
Making a copy of your DOS Diskette should be one
of the first things you do with your IBM Personal
Computer after you get DOS. That way you won't be
"shut down" if your DOS Diskette becomes misplaced
or accidentally damaged. This copy is called a "back-up"
and making the copy is usually called "backing up."
Before You Begin
You will need:
• Your DOS Diskette.
• A diskette, preferably brand new, that will become
the back-up. (If the diskette has been used before,
make sure that it does not contain information you
will need again. This procedure will destroy any
information that was stored on the diskette.)
We will refer to this diskette as the "back-up"
diskette in the two examples that follow.
Read through the instructions before you start. There
are two sets of instructions depending on whether you
have one diskette drive or two.
DOS 3-23