CLASSIFICATION OF COMPUTERSstudentsfounder.com/wp...No.-02-Classification-according-to-logic-si… · 1 CLASSIFICATION OF COMPUTERS According to function/logic use: 1. Analog computer

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CLASSIFICATION OF COMPUTERS

According to function/logic use:

1. Analog computer

2. Digital computer

3. Hybrid Computer

1. ANALOG COMPUTERS are that in which data varies continuously i.e. the

movement of data is continuous.

REPRESENTED BY: series of waves

OR

An analog computer is a form of computer that uses the continuously changeable

aspects of physical phenomena such as electrical, mechanical, or hydraulic quantities to

Model the Problem being solved.

Polish Analog computer:

USED FOR

Measuring temperature, pressure, etc

Communication

Broadcast transmission

EXAMPLE

Automobile Speedometer, Voltmeter, etc

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2. DIGITAL COMPUTERS:

Digital Computers are those computers in which data flows in discrete form.

REPRESENTED BY: Pulses, two series i.e. 0s & 1s

OR

Digital computer, any of a class of devices capable of solving problems by processing

information in discrete form. It operates on data, including magnitudes, letters, and

symbols, that are expressed in binary form—i.e., using only the two digits 0 and 1.

OR

Computer that stores data in terms of digits (numbers) and proceeds in discrete steps from

one state to the next. The states of a digital computer typically involve binary digits

which may take the form of the presence or absence of magnetic markers in a storage

medium, on-off switches or relays. In digital computers, even letters, words and whole

texts are represented digitally.

USED FOR

Mathematical calculations

Compare values

Storing the result

EXAMPLE

Digital watch, Education system, business purpose

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3. HYBRID COMPUTERS

Hybrid Computers are combination of both analog computer and digital computer

MEASURES: both continuous and discrete form of data

OR

Hybrid computers are computers that exhibit features of analog computers and digital

computers.

OR

Computers that exhibit features of analog computers and digital computers. The digital

component normally serves as the controller and provides logical operations, while the

analog component normally serves as a solver of differential equations.

EXAMPLE

STD/PCO phone, where one communicate with a person using analog computer & the

rate as charges and pulse rate is measured in forms of digit or A petrol pump contains a

processor that converts fuel flow measurements into quantity and price values.

In hospital Intensive Care Unit (ICU), an analog device is used which measures patient's

blood pressure, heart beat or ECG, and temperature etc, which are then converted and

displayed in the form of digits.

Hybrid Computers:

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Digital Computer Classification according to purpose:

General Purpose Computer

Special Purpose Computer

GENERAL PURPOSE COMPUTER:

These are designed to perform the variety of jobs or applications for this reason; they are

less efficient than special purpose computers.

EXAMPLE

Banking, Sales Analysis, PCs, etc

SPECIAL PURPOSE COMPUTER:

These are designed to meet the needs of some special application. They are designed to

perform a single job. So they execute a task quickly and more efficiently. Program and

instructions are stored permanently in them.

EXAMPLE:

Weapon designing

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Digital Computer Classification according to sizes:

1. Super Computer

2. Mainframe Computer

3. Mini Computer

4. Micro Computer

5. Desktop Computer

6. Pocket Computer

1. SUPER COMPUTER:

The fastest type of computer, Supercomputers are very expensive and are employed for

specialized applications that require immense amounts of mathematical calculations. For

example, weather forecasting requires a supercomputer.

PURPOSE: Special purpose computers handle mostly complex scientific, statistical

applications or programs.

KEY FEATURES

High technology

High capacity memory i.e. 8.4 million

Computes data processing in short time

Highly sophisticated technology

Cost varies from 1 million to 5 million

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EXAMPLE:

1. Titan:-

The fastest supercomputer in the world is used to study alternative energy resources and

climate change simulations in a global level.

2. Sequoia:-

This one’s a life saver. USA doesn’t have to actually conduct nuclear tests anymore,

Sequoia simulates them. This one makes sure that the nuclear weapons are ready for

action any time of the day.

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3. IBM Mira:-

Mira by IBM, simulates the evolution of the Universe. It also runs the climate change

scenarios and helps in research of more efficient car batteries.

Super computer in India:

• India’s first super computer is PARAM yuva II

• I Data Plex DX360M4

• Cluster Platform 3000 BL460c Gen8

• SAGA - Z24XX/SL390s Cluster

• EKA

DRAWBACK

Operating Supercomputer requires highly qualified staff.

Experts were required for such computer engineering.

They are sensitive to temperature, humidity, dust, etc.

Non portability & large size

2. MAINFRAME COMPUTERS:

The term referred to the large cabinets that housed the central processing unit and main

memory of early computers. Modern mainframes can run multiple different instances of

operating systems at the same time.

KEY FEATURES

Smaller size than super computer

Large memory capacity

Allows networking of up to 100 terminals

Cost varies from 5-20 lacs.

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EXAMPLE

1. IBM System 3:

2. AS-400:

3. PDP-370, IBM 40

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DISADVANTAGES

Experts and highly qualified professionals were required to operate it

Sophisticated technology required for manufacturing & assembling the computer

3. MINI COMPUTER:

A minicomputer, or colloquially mini, is a class of smaller computers that evolved in the

mid-1960s. They use of transistors and core memory technologies, minimal instructions

sets and less expensive peripherals such as the ubiquitous Teletype Model 33 ASR.

KEY FEATURES

Higher processing speed than lowest category computer but slower than super computer

& Mainframe computer

Portable computers because of smaller size

Memory capacity RAM is up to 128 MB

Secondary Memory store 40 GB

Costs around Rs 50 thousand to 90 thousand

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EXAMPLE:

1. The first successful Western minicomputer was Digital Equipment Corporation's 12-bit

PDP-8, which was built using discrete transistors and cost from US$16,000 upwards

when launched in 1964.

2. The 7400 series of TTL integrated circuits started appearing in minicomputers.

3. PDP-11 and PDP-45 etc.

DISADVANTAGES

Cannot connect all hardware devices

Cannot execute all languages and software

4. MICRO COMPUTER:

A microcomputer is a small, computer with a microprocessor as its central processing unit

(CPU).Microcomputers became popular in the 1970s and 80s with the advent of increasingly

powerful microprocessors.

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KEY FEATURES

Smaller than Mini Computer

High speed computer but slower than mini computer

Costs around Rs 30000 to 60000

Portable

RAM requires 64 MB to 128 MB

Limited languages FORTRAN, Basic, COBOL, Pascal can be executed

EXAMPLE

1. ECD Micro mind:

2. Data point 2200:

3. Uptron, HCL, PCL, Wipro, PCs, HP, PC-AT, PC-XT

DRAWBACKS

Limited Hardware devices can be connected

Experts were required

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5. DESKTOP COMPUTERS:

A Desktop computer is a personal computer in a form intended for regular use at a

single location, as opposed to a mobile laptop or portable computer.

PURPOSE: Education system and small scale industry

CALLED: HOME or Briefcase Computers

KEY FEATURES

Portable

High speed processing processor varies from 80286 to 80586

Requires RAM from 16 MB to 64 MB

Internet facility for communication

Costs around Rs 30,000 to Rs 60,000

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EXAMPLE

HCL, PCL, Wipro, COMPAQ, HP, LEO, SAMSUNG, etc

DISADVANTAGES

Execute limited software and languages related to windows based

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6. POCKET COMPUTER

KEY FEATURES

Small in size

Portable like a digital diary

Requires RAM maximum up to 1GB

Disk capacity is 80 GB

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DISADVANTAGE

Execute limited Software