The document categorizes computers into four main types: micro computers, mini computers, mainframe computers, and super computers, each with distinct features and purposes. Micro computers include personal computers and portable devices like laptops, notebooks, and tablets, while mini computers serve as midrange servers. Mainframe and super computers are designed for large-scale data processing and complex calculations, with the latter being the fastest and most expensive.

1. 1st Sem B.Com Computer Application
Kerala University
Introduction to Information Technology
Module - 2
Lecture -1
Classification of Computers
Classification of computers
1. Micro Computers
2. Mini Computers
3. Mainframe computers
4. Super computers
• Workstation
• Servers

2. Classification of Computers
• A computer is an electronic device used to store, retrieve and process the data.
• As technology continuous to progress the computer has been modified into
different shapes, with varied features and a wide range of purposes.
Based on their size, performance and capacity computers are classified as follows.
1. Micro computers
2. Mini computers
3. Mainframe computers
4. Super computers

3. 1. Micro Computers
• A micro computer is a general purpose computer, simple and small type of
computer.
• They can do a variety of jobs such as storage of data, calculations, control and
output.
• Micro computer is meant for single individual.
• Micro computers are available in different forms and types.

4. Personal Computers (PC)
• A PC can be defined as a small, relatively inexpensive computer designed for an
individual user.
• PCs are based on the microprocessor technology.
• PCs can be used for both business and home use.
A personal computer can be of different types →→→

5.  Desktop Computers
• Today desktop computers are the most popular computer system.
• They can be small, medium or large in style and the usually put on a table top or
desk.
• It is simply any computers used for general purpose meant to be used by an
individual person at time.
-Advantages
• Cheaper
• Easier to upgrade
• Faulty accessories and components are easy to replace
-Disadvantages
• High power consumption
• Covers more space
• Not easy to carry out

6.  Laptop Computers
• Laptop computers are small portable computers.
• They are light computers with a thin screen
• They can operate on batteries.
-Advantages
• Light weight
• Portable
• Power consumption is very low.
• It can be operate on batteries.
-Disadvantages
• High cost
• Less powerful than desktop of the same price range.
• Because of the style prolonged use of laptop can cause health problems.

7.  Notebook Computers
• It is an extremely lightweight portable computer, which easily fit in a
brief case.
• In terms of computing power, modern notebook computers are
nearly equivalent to personal computers

8.  Subnotebook Computers
• A portable computer slightly lighter and smaller than a full sized note book
computer.
Handheld Computers
• Handheld computers or Personal Digital Assistants(PDAs) are pen based and also
battery powered.
• They have touch screens.
• They are small and can be carried anywhere.
• They use a pen like stylus and accept handwritten input directly on the screen.
• They are used for scheduling appointments, storing address, playing games etc…

9.  Palmtop (Pocket computers)
• Palmtop is a small computer that fits in your palm.
• It can be used for certain functions such as phone book and calendars,
schedulers etc.
• Most palmtop computers do not include disk drives.
Tablet Computers
• A tablet uses a touch screen as its primary interface and it is the lightest and
most portable computer.
• Most tablet brands offer 3G or 4G connectivity.
• Longer battery life than laptop.
• They have low power processors.
• Storage is fixed and memory card slots are available for expansion.

10.  Wearable computers
• These are miniature electronic devices that are worn by the bearer under, with or
on top of clothing.
• Common computer applications such as e-mail, database, multimedia etc. are
integrated into watches, visors and even clothing.
Embedded Computers
• Embedded computers are computers that are a part of a machine or a device.
• Embedded computers are generally execute a programme that is stored in non
volatile memory and is only intended to operate a specific machine or device.
• They are typically required to operate continuously without being rest or
rebooted and once employed in their task, the software usually can not be
modified.

11. 2. Mini Computers
• Mini computer is a medium size computer that is more powerful,
faster and costlier than micro computers.
• These are mainly used as small or midrange servers operating
business and scientific applications.

12. 3. Mainframe Computers
• Mainframe computers are capable of handling and processing very
large amount of data very quickly.
• The speed of mainframes is expressed in million instructions per
second(MIPS).
• They are very large and expensive computer capable of supporting
hundreds or even thousands of users simultaneously.
• They are used in banks, airline, railway etc.

13. 4. Super Computers
• It is a high performance computing machine designed to have
extremely fast processing speeds.
• One of the fastest computer currently available.
• It can process billions of instructions per second.
• They are very expensive and are employed for specialized application
that require immense amount of mathematical calculations.

14. Workstations
• A workstation is simply a desktop computer that has a more powerful
processor, additional memory and enhanced capabilities for
performing a special group of task such as 3D Graphics or game
development.
• Workstations are generally comes with a large, high resolution graphic
screen, large amount of RAM, inbuilt network support and a graphical
user interface.

15. Servers
• The server’s main purpose is to provide certain services to other
computers or a whole network of other computers.
• It has powerful processor, additional amount of memory and bigger
hard drives.
• Server also play important role in making the internet work.
• They are where webpages are stored.