Operating System (DOS) - provides the commands to control
peripheral devices such as disk drives - format, copy, open, save,
delete, print, etc. Examples are MS-DOS, OS/2 and UNIX (only one
of these is needed on a computer). It is usually preinstalled as files on the hard
disk and therefore easy for the user to upgrade.
Operating System (CMOS) - controls the basic machine when it
is switched on, telling it how to communicate initially with its
various parts (hard disk, keyboard, etc) and is unlikely to need upgrading. Usually stored
in a ROM chip.
Line Interpreter (CLI) - provides an interface between a
human operating system (your brain) and the computer's operating
system through the use of commands which have to be typed in at
the keyboard onto a blank screen. For example: COPY C:\REPORT.DOC
A: would copy a file called report.doc from the hard drive (C:)
to the floppy drive (A:). These commands are provided as part of
the operating system package and have to be learnt and remembered
accurately by the user. Fortunately this is no longer absolutely necessary - see
User Interface (GUI) - provides an interface between a human
operating system (your brain) and the computer's operating system
through the use of pictures (as icons) and text (as menu options)
provided on the screen. Examples are MS Windows
95 or 98 which include MSDOS as one complete package. All new computers
now have an operating system and GUI pre-installed. Modern
computers are now much easier to use as complicated commands no
longer need to be learnt by the average user.
or Tools - programs which perform various management tasks.
Examples are Pkzip or Winzip, which will compress files so that
they are small enough to fit onto a floppy disk or transmit
faster over the internet. Antivirus software which will run in the
background and zap any viruses as soon as they appear. Quickres
is a program that allows you to change your screen resolution
without restarting the computer.
- programs which provide a translating interface between commands
used by the operating system and commands used by your various
hardware devices such as printer, scanner, monitor, modem, mouse, etc. These devices are produced by a wide range of
different companies and are continually being updated and
improved. An operating system will include many common drivers
that were available at the time you purchased the computer. If
you later buy a new device such as a printer, it will often be designed
to work with the old drivers, but you will get more out of it if
you install the new drivers that are provided by the manufacturer.