2. Objective:
On completion of this period, you would be
able to know:
The generations of computers.
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3. Generations of computers
The first generation computers
The second generation computers
The third generation computers
The fourth generation computers
The fifth generation computers
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4. The First Generation Computers.
The digital computer using electronic device
(vacuum tubes) is known as the first generation
computer.
The first generation computer used vacuum tube
as a CPU component.
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5. The first generation computers (contd):
Vacuum Tube is the main technology
Acoustic delay lines were used for memory
These are costly but slower devices
Larger in size
Produced more heat
Maintenance was needed
Highly unreliable.
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6. The first generation computers (contd):
They used fixed-point arithmetic
Examples : IBM 700 series – IBM 701, IBM 704,
IBM 709, EDVAC and UNIVAC.
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7. The second generation computers
The second generation computers used
transistors as CPU components
Ferrite cores for main memory and magnetic
disks and tapes for secondary memory.
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8. The third generation computers
The third generation computers used ICs (SSI
and MSI) as CPU components.
These used magnetic core memory, but later on
semiconductor memories.
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9. The third generation computers (contd)
Semiconductor memories were LSI chips.
Concept of Cache memory was introduced.
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10. The third generation computers (contd)
Micro programming, parallel processing, multi
processing, multi user system and time sharing
system etc were introduced.
Examples:IBM/370 series (1970),CDC 7600
(1969), CDC’s CYBER-175 and STAR-100,etc
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11. The fourth generation computers
Fourth generation computers use VLSI chips for
CPU, memory and supporting chips.
They use microprocessor as CPU (32 bit or 64
bit).
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12. The fourth generation computers (contd)
They also contain many other essential
components such as FPU (Floating Point Unit),
MMU (Memory Management Unit), first level and
second level cache memory etc.
Examples of latest microprocessors :Pentium II
and Pentium III, Power PC ,DEC’s Alpha, SUN’s
ULTRASPARC ,AMD’s K-6,K-7,etc
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13. The fifth generation computers (contd) :
The fifth generation computers are under
development stage.
These computers will use ULSI (ultra large scale
integration) chips.
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14. The fifth generation computers (contd) :
ULSI chips contain millions of components into a
single IC.
The input and output information for these
computers will be in the form of speech and
graphic images
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15. The fifth generation computers (contd) :
The computer will understand natural languages
like English , Japanese , etc.
The programmers will not have to learn
programming languages.
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16. The fifth generation computers (contd) :
They will be able to speak commands or key
information in their mother tongue
Vision system will also be incorporated.
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17. GENERATIONS OF COMPUTERS
Generations Components Advantages Disadvantages Examples
used
First (1946- Vacuum tubes Machine Language Costlier, more IBM700,ENIAC,
1954) space, excess EDVAC
power
Second(1955- Transistors Less expensive, less Used Assembly IBM7090,
1964) power, Language IBM7094 I,
Cheaper & small in IBM9094 II
size
Third(1965- Integrated circuits, Smaller, Faster, IBM/370 series,
1974) Semi conductor Cheaper - Cyber175
memory
Fourth(1975- VLSI chips Faster, Less power Uses one or more CRAY Y_MPC,
1984) consumption microprocessors WIPRO
LANDMARK
860
Fifth(1985- ULSI Very high - Windows 2000,
present) performance, Easy Xp, Linux
access,
Multiprocessing
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18. Summary
In this class, we have learnt about
Generations of computers
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