Technical Fresh Guru

Technical Fresh Guru

Classification of Digital Computers | Basic Computer Skills


In the previous posts, we covered some topics, including an Introduction
to computers, Uses of computers, Characteristics of computers, History of
computers, Generation of computers, and Types of Computers in this post we will
also cover the main topic of Classification of Digital Computers, and this post is
also made on basic computer skills. For people who are beginners in the realm
of computers, this post will be very helpful.

We’ll discuss and cover the following topic. Visit “BasicComputer Course Lesson 3” on our YouTube Channel.

You also review our previous posts given below:

of Digital Computers

Digital Computers are
classified according to size, speed, and memory capacity, Computers are of
different types:

  • Supercomputer
  • Mainframe Computer
  • Mini Computer
  • Micro /PC Desktop Computer


Supercomputers are very fast
computers that can perform hundreds of millions of instructions per second.
These are the fastest calculating devices. These computers are used by
government agencies. A supercomputer is typically used for scientific and
engineering applications that must handle a very large database or do a great
amount of computation (or both).


IBM’s Roadrunner is the fastest
supercomputer in the world, twice as fast as Blue Gene and six times as fast
as any of the other current supercomputers. At the lower end of supercomputing,
a new trend called clustering takes more of a build-it-yourself approach to

The best-known builder of supercomputers
has been Cray Research, now a part of Silicon Graphics. In September 2008, Cray
and Microsoft launched CXI, a $25,000 personal supercomputer aimed at markets such
as aerospace, automotive, academic, financial services, and life sciences.


  • Some scientific problems and
    processes are so complex that you need supercomputers to tackle them.
  • Climate researchers model Earth’s
    current and predicted future climate using supercomputers.
  • Astronomers and space scientists
    use supercomputers to study the Sun and space weather.
  • Scientists use supercomputers to
    simulate how a tsunami would impact a coastline or a given city.
  • Supercomputers are used to
    simulate supernova explosions in space.
  • Supercomputers are used to test
    the aerodynamics of the latest military planes.
  • Supercomputers are being used to
    model how proteins fold and how that folding might affect people that have
    Alzheimer’s disease, Cystic Fibrosis, and many kinds of cancer.
  • Supercomputers are used to model
    nuclear explosions. Limiting the need for real nuclear testing.

Mainframe Computers

Mainframe is an industry term for
a large computer. The name comes from the way the machine is built up: all
units (processing, communication, etc.) were bung into the frame. Thus the main
computer is built into a frame, therefore it is called a Mainframe.

Because of the high development
costs, mainframes are typically manufactured by large companies such as IBM,
Amdahl, and Hitachi.

Use of the Mainframe Computers:

Mainframe computers are used to
run commercial applications and other large-scale computing purposes. It is
also used in banking and insurance businesses where enormous amounts of data
are processed, typically (at least) millions of records, each day.

Mini Computers

Minicomputers are introduced in
the early 1960s and announced a new era in computing. They are relatively low
cost and small. This setup allowed more people to have access to computers and
as a result, an era of new applications in universities, industry, and commerce
are created. 

Digital Equipment Corporation developed the PDP-1minicomputer in
1960, and the PDP-8 virtually conquered the market in a sweep and sold over
40,000 units. In time some 200 companies produced this type of minicomputer.
DEC got at the top of the market with the PDP-11, and with the VAX 11/780 system.
The latter will become a landmark system in the history of computing.

Uses of Mini Computers:

  • They offer a limited range of
  • Limited software can be used.
  • There is a facility for the direct
    operation of the machine by the end user.
  • Air conditioning is not necessary
    for minicomputers.

Micro / PC/ Desktop Computers

The term “Microcomputer” came
into popular use after the introduction of the minicomputer. The earliest
models were often sold as kits to be assembled by the user and came with as little
as 256 bytes of RAM, and no input/output devices other than indicator lights
and switches, useful as a proof of concept to demonstrate what such a simple
device could do.

However, as microprocessors and
semiconductor memory became less expensive microcomputers in turn grew cheaper
and easier to use:

Increasingly inexpensive logic
chips such as the 7400 series allowed cheap dedicated circuitry for improved
user interfaces such as keyboard input, instead of simply a row of switches to
toggle bits one at a time.

These computers are used nowadays
commonly and these computers revolutionized the computer industry because of
their size and cost.

Some of the features are:

Cheap and easy to use: Microcomputers are cheap and easy to use.

Limited support for I/O Devices:
They support very limited input and output capacities.

Storage Capacity: They have less
storage capacity.

Software Support: These computers
support a very limited number of software.

Architecture: Most microcomputers are self-contained units, which are light enough and can be
moved easily.

Number of Operators: They are
designed to be used by one person at a time.

I/O Devices: In addition to the
CPU (central processing unit), a microcomputer has an operator keyboard for

Data Storage: Hard disk and
floppy disk drivers are used to enter and store data and programs.

Softcopy Output: A visual display
screen and/or a printer is used to get the output.

Use of the Microcomputers

These are the most sold computers
in the world. They are used for various applications ranging from business to
engineering designs. They are also used by millions of people all over the
world for entertainment and personal applications.

The types of microcomputers are:

  • Desktop Computers
  • Laptop Computers
  • Palmtop Computers

Desktop Computers

Today desktop computers are
those computers that have different desktop computer cases that can be
laid on the desk and they are different from tower computers based on the design of the case as in tower computers the CPU stand straight. 

today desktop computers have different monitors and keyboard systems as
compared to the earlier computers which have all the systems combined with each
other. There are various such computers available like the AMD desktop computers.

Laptop Computers

A Laptop is a personal computer
designed for mobile use. It is small and light enough to sit on a person’s lap
while in use. A laptop integrates most of the typical components of a desktop
computer, including a display, a keyboard, a pointing device (a touchpad, also
known as a trackpad, and/or a pointing stick), speakers, and often including a
battery, into a single small and light unit. 

The rechargeable battery (if
present) is charged from an AC adapter and typically stores enough energy to
run the laptop for two to three hours in its initial state, depending on the
configuration and power management of the computer.

Palmtop Computers

A computer small enough to hold
in one hand and operate with the other. Also called a “handtop,” these
ultra-small computers may have specialized keyboards or keypads for data entry
applications or have small QWERTY keyboards.

Because of their small size, most
palmtop computers do not include disk drives. However, many contain PCMCIA
(Personal Computer Memory Card International Association) slots in which you
can insert disk drives, modems, memory, and other devices.


We have created this post for the
newbies who are beginners to a computer course. It is designed to develop basic
computer skills to enhance your knowledge. Also, you can review our posts on “What is Computer”, “History of Computer”, and “Computer Hardware and Software”. If there
is any kind of lack in this post or if liked it, please comment to us. Thanks

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