The document discusses different types of computers based on their principles of operation and configuration/size. It describes the Von Neumann architecture, which is a design model for stored-program digital computers that uses a single memory to hold both instructions and data. The types of computers covered include analog computers, digital computers, and hybrid computers based on their operating principles. Based on configuration, the types discussed are super computers, mainframe computers, mini computers, and micro computers including desktops, laptops, and handheld devices.

1. Instructor : Muhammad Hammad Waseem
Email: m.hammad.wasim@gmail.com

2. Muhammad Hammad Waseem 2
• The Von Neumann Architecture and its
figure
• Important Features of the Von Neumann
Architecture

3. 
 The Von Neumann architecture is a design model for
a stored-program digital computer. Its main
characteristic is a single separate storage structure
(the memory) that holds both program and data.
 Von Neumann computer architecture, which is
illustrated in the following figure:
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The Von Neumann
Architecture
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4. 
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The Von Neumann
Architecture (cont…)

5. 
 both instructions (code) and data (variables and
input/output) are stored in memory;
 memory is a collection of binary digits (bits) that
have been organized into bytes, words, and regions
with addresses;
 the code instructions and all data have memory
addresses;
 to execute each instruction, it has to be moved to
registers;
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Important Features of Von
Neumann Architecture
Muhammad Hammad Waseem

6. 
 only the registers have the “smarts” to do anything
with the instructions; memory locations have no
“smarts”;
 to save a result computed in the registers, it has to be
moved back to memory;
 operating systems and compilers keep the
instructions and data in memory organized so it
doesn't get mixed up together;
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Important Features
(Cont.)

7. 
TYPES OF
COMPUTERS
• Introduction
• Types based on Principle of operation
• Analog computers
• Digital computers
• Hybrid computers

8. 
 Computers can be classified based on their principles
of operation or on their configuration. By
configuration, we mean the size, speed of doing
computation and storage capacity of a computer.
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TYPES OF COMPUTERS
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9. 
 There are three different types of computers
according to the principles of operation.
 Those three types of computers are:
 Analog Computers
 Digital Computers
 Hybrid Computers
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Types based on
Principles of Operation
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10. 
 Analog Computer is a computing device that works
on continuous range of values.
 The results given by the analog computers will only
be approximate since they deal with quantities that
vary continuously.
 It generally deals with physical variables such as
voltage, pressure, temperature, speed, etc.
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Analog Computers
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Examples
• Speedometer
• Weight machine
• Thermometer
• Temperature
• Speed
Analog watch
Applications
• Engineering
• Scientific Work
• To control process
• Chemical industries
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Advantage & Disadvantages
Of Analog Computer
ADVANTAGE OF ANALOG COMPUTERS
• Analog computers are fast.
DISADVANTAGES OF ANALOG COMPUTERS
• Analog computers are not accurate.
• Analog computers lack memory.

13. 
 On the other hand a digital computer operates on
digital data such as numbers.
 It uses binary number system in which there are only
two digits 0 and 1. (a bit)
 Digital Computers can give more accurate and faster
results.
 Digital computer is well suited for solving complex
problems in engineering and technology.
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Digital Computers
Muhammad Hammad Waseem

14. 
 Hence digital computers have an increasing use in
the field of design, research and data processing.
 Based on the purpose, Digital computers can be
further classified as:
 General Purpose Computers:
 Used for any type of applications.
 Special Purpose Computers:
 One that is built for a specific application.
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Digital Computers (Cont…)

15. 15
Examples
• Calculators
• Accounting machines
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Applications
• Scientific research
• Business
• Education
• Factories
• Market
• Art
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Advantage & Disadvantages
Of Digital Computer
ADVANTAGES OF DIGITAL COMPUTERS
• Digital computers are accurate.
• Store information.
DISADVANTAGES OF DIGITAL COMPUTERS
• Digital computers are slow as compared to
Analog computers.
Muhammad Hammad Waseem

18. 
 A hybrid computer combines the desirable features
of analog and digital computers.
 It is mostly used for automatic operations of
complicated physical processes and machines.
 Now-a-days analog-to-digital and digital-to-analog
converters are used for transforming the data into
suitable form for either type of computation.
 Hybrid computers are mainly used for specialized
tasks.
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Hybrid Computers

19. 
 It combines the best features of both digital and analog.
 Hybrid computers have the accuracy of analog and speed
of digital computers
Applications
 In hospitals
 In Air Defence system
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Advantages Of Hybrid
Computers

20. 
Types of Computers
based on Configuration
/ Size
• Types of Computers based on Configuration / Size
• Super computers
• Mainframe computers
• Mini computers
• Micro computers
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21. 
 There are four different types of computers when we
classify them based on their performance and
capacity. The four types are
 Super Computers
 Mainframe Computers
 Mini Computers
 Micro Computers
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Types of Computers based
on Configuration / Size

22. 
 They are the best in terms of processing capacity and
also the most expensive ones.
 These computers can process billions of instructions
per second.
 Perhaps the best known super computer
manufacturer is Cray Research.
 Some of the "traditional" companies which produce
super computers are Cray, IBM and Hewlett-
Packard.
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Super Computers

23. 
 Weather forecasting
 Stock analysis
 Nuclear research
 Designing complex
machines
 Scientific simulations
 (animated) Graphics,
analysis of geological
data
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Applications & Uses

24. 
 Mainframe computers can also process data at very
high speeds i.e., hundreds of million instructions per
second and they are also quite expensive.
 They are large in size and occupy the space of a
room.
 Need cooling requirements as well.
 Perform multiple jobs and support hundred of users.
 Normally, they are used in banking, airlines and
railways etc. for their applications
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Mainframe Computers

25. 
 Mini computers are lower to mainframe computers
in terms of speed and storage capacity.
 They are also less expensive than mainframe
computers.
 Some of the features of mainframes will not be
available in mini computers. Hence, their
performance also will be less than that of
mainframes.
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Mini Computers

26. 
 The invention of microprocessor (single chip CPU)
gave birth to the much cheaper micro computers.
They are further classified into
 Desktop Computers
 Laptop Computers
 Handheld Computers(PDAs)
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Micro Computers

27. 
 Today the Desktop computers are the most popular
computer systems. These desktop computers are also
known as personal computers or simply PCs.
 They are usually easier to use and more affordable.
 They are normally intended for individual users for
their word processing and other small application
requirements.
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Desktop Computers

28. 
 Laptop computers are portable computers.
 They are lightweight computers with a thin screen.
 They are also called as notebook computers because
of their small size.
 They can operate on batteries and hence are very
popular with travellers.
 The screen folds down onto the keyboard when not
in use.
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Laptop Computers

29. 
 Handheld computers or Personal Digital Assistants
(PDAs) are pen-based and also battery-powered.
 They are small and can be carried anywhere.
 They use a pen like stylus and accept handwritten
input directly on the screen.
 They are not as powerful as desktops or laptops but
they are used for scheduling appointments, storing
addresses and playing games.
 They have touch screens which we use with a finger
or a stylus.
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Handheld Computers