DOS is a special program which comes
with your computer. It's primary
purpose is to run other programs.
With DOS, you cannot write a letter,
add up numbers or draw a picture. But
because of DOS, you can run programs
for writing, math or drawing.
    After the computer starts, DOS
provides a command line, a place on
the screen where you can type a line
of text telling DOS what to do.  At
the start of the command line is a
prompt, often called the "C Prompt."
It looks like this:

C:\>_

    The C means that the currently
"logged" or active disk is C, the
hard disk. If your computer has one
or more floppy disk drives, they are
A and B.  If there is a CD-ROM, or
more than one hard disk, they are D,
E and so on.

   To run a program from the command
line, you simply type it's filename,
then press the [Enter] key.  For
instance, if you have a game called
STARS, then you type STARS, press
[Enter], and STARS will begin and
take over control of your computer.
When you are done playing STARS, the
C Prompt reappears and you can type
something else on the command line.

   DOS has other functions in
addition to support for running
programs. With DOS you can display a
list of the files on a disk, and you
can copy, rename and delete files.
There are actually several more
services available, but these are the
important ones.

                 DIR

In order to work with files, you need
to know what you have. DIR will list
the files on a disk.  To use DIR,
type DIR followed by a space, then
the letter of the disk containing the
files you want to list and finally a
colon before pressing the [Enter]
key. Example:

DIR A:

This will show the files on the
floppy in the A drive.

If there are more files that will fit
on the screen at one time, type

DIR A:/P

The /P will pause the list so you can
view the files one screenful at a
time.

DIR accepts "filters."  A filter is a
means of limiting the files which
will be displayed.

This example will show only one file,
if it exists on the disk:

DIR C:FROG.EXE

The asterisk (*) is a wildcard
specifier. If you place an asterisk
on one side of the period (called
"dot" in computer talk) in a file
name, then all files matching the
other part of the filename will be
displayed:

DIR C:*.EXE

This above example would list all
files ending in .EXE.

DIR C:FROG.*

This example will show all files
which start with FROG, and no other
files.

You can use an asterisk in
combination with a portion of a
filename also.  For instance the
example below:

DIR C:FROG*.EXE

might show these files:

FROG1.EXE
FROG.EXE
FROGLEG.EXE

    DIR gives you valuable
statistics. At the end of every
listing you get a number of bytes
free, showing how much space is left
on the disk.  After each file is it's
size in bytes, and the date and time
it was created or last modified.

                COPY

Copy is a very useful service.  Since
things may happen, and the
information you can store on a
computer's hard disk may be very
important, with Copy you can make
backup copies of your information on
floppy disks for safe storage.

    Unlike video tapes, which degrade
from one generation of copies to the
next, each time you copy computer
data from one disk to another, it is
as well defined as the original.

   To use Copy, you specify the
source file, then the destination
file. Just like dishes, you have to
pick them up off the floor, before
you can set them in the sink.

Here is an example:

COPY C:CHESS.EXE A:CHESS.EXE

DOS allows some assumptions to be
made so that you can reduce the amount
you have to type on the command line.
    If you want the copy of the file
to have the same name as the
original, you do not need to spell
out the filename twice:

COPY C:CHESS.EXE A:

    If you are copying from the
logged disk,  then you do not need to
specify the source disk letter:

COPY CHESS.EXE A:

These last two examples work as well
as the first.

   You can use wildcards with the
Copy command.  The following command
will copy all files beginning with
CHESS to a floppy disk:

COPY CHESS.* A:

This may result in several files
being copied, for instance:

CHESS.EXE
CHESS.DOC
CHESS.1
CHESS.2

You can even copy everything at once
with this:

COPY A:*.* C:

The above example copies everything
from the floppy disk in drive A to
the hard disk.

              COPY PRN

Copy can do more than copy files from
one disk to another.  Text files can
also be copied to the printer.  Text
files come in many flavors, depending
on the programs which were used to
create them, but there is a standard
called ASCII files.  ASCII is used by
programs which must interact with
DOS, and is the format used for
on-disk instructions offered with
many programs.
    Many ASCII text files end with
.DOC, .TXT, .ME or .1ST.
    You can copy an ASCII text file
to the printer by specifying PRN as
the destination.  Example:

COPY TOADS.TXT PRN

       [SHIFT] [PRINT SCREEN]

If you hold down either [Shift] key
and press [Print Screen] whatever is
currently shown on the computer
monitor will be printed to paper.
This works best with text-only
programs. The results when using
[Shift] [Print Screen] with graphics
will vary with the type of printer
you have and any software you may be
currently running.

                 REN

REN renames files. Example:

REN FROGS.TXT TOADS.TXT

The file which used to be called
FROGS.TXT will become TOADS.TXT.

                 DEL

DEL deletes files.  This is good,
because your disks can eventually
become full.  This is also dangerous
because there are few safeguards.
You can accidentally delete important
files. (A good reason to use Copy and
make back-ups on floppy disks
frequently.)  To use DEL, simply type
DEL followed by a space then the name
of the file you want to get rid of:

DEL TOADS.TXT

In the above example TOADS.TXT
disappears off the face of the earth
forever.

With DEL you can also use wildcards.

Guess what happens if you type:

DEL *.*

Hint: Don't try this unless you have
backed up ALL your files!  Still,
don't try it!

                TIME

If you type TIME on the command line,
you get the current time.  Press
[Enter] when done viewing the time.
If you want to reset your computer's
clock, type in a new time before
pressing [Enter].  DOS keeps time in
24-hour format.  To set for 8pm, you
type:

20:00:00

since pm times are am times plus 12
hours.

                DATE

Date is just like time, but is for
viewing or setting the date. Place
dashes between the month, day and
year.  Months earlier than October
and days earlier than the 10th are
typed with a leading zero.  The year
is typed with just the last two
digits.  To set April 2, 1996, type:

04-02-96

        [CTRL] [ALT] [DELETE]

Situations in which the computer has
a runaway failure and no longer
responds are surprisingly common. The
usual cause is a loop in which the
computer is trying to perform some
invisible task over and over again
and gets so busy that you can't break
in to stop it.
    The most common reason is that
you have typed a command that the
current program you are using is not
equipped to handle.  Often this is
the fault of the program, not the
user.  Modern software is very
complex, with an almost unlimited
number of possible events to handle.
    A typical such case is where you
have asked the program to make a
paper copy, but the printer's power
switch is turned off.  The program
will keep sending data to the printer
until the page is printed, even if it
takes forever! Even the best, most
expensive programs can fail
sometimes.
    Anyway, there are four ways you
might be able to break the loop:

1. Press the [Esc] key.  Esc stands
for "escape" and this key is a way
to get out of trouble, to decline
options, to answer questions
negatively, or to return to a
previous level of choices.

2. If [Esc] does not work then hold
down the [Ctrl] key and press the
[Pause/Break] key.

3. If [Ctrl] [Break] doesn't do it,
try holding [Ctrl] while you press
the [C] key.

4. If [Ctrl] [C] doesn't do it, hold
down the [Ctrl], [Alt] and [Del] keys
simultaneously. This is called
"re-booting" and will cause the
computer to drop everything, and
restart from scratch.

5. In the rare case where [Ctrl]
[Alt] [Delete] doesn't even work,
turn off the power to your computer,
wait 30 seconds, then restart.

              MD/CD/RD

CD stands for Change Directory.  MD
stands for Make Directory.  RD stands
for Remove Directory.  Since modern
hard disks can hold thousands of
files, DOS provides a system of
directories which are like
folders in a filing cabinet.  Each
directory can hold many files, which
are separated from the files in other
directories on the same disk.  For
more information on Directories,
return to the menu and see
DIRECTORIES.

____________________________________
                        end of file.


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