2. A “Brief” History
Abacus considered first
mechanical computing
device.
Used beads and rods to
count numbers.
Developed around
3000 B.C.
3. Mechanical Calculator
1612 – John Napier used
floating point arithmetic and
invented the logarithm.
1622 – William Oughtred
created the slide rule based
on Napier’s logarithms. This
was the primary calculator
used by engineers until the
1960’s.
4. 1642 – Blaise Pascal
created a machine that
could add and subtract,
automatically carrying
numbers.
1673 – Gottfried Leibnitz
built a calculator that
could multiply and divide
as well.
5. 1790 – Joseph Marie
Jacquard invented an
automatic loom using
punched cards to
control patterns in the
fabrics.
Punched cards were
used to allowed some
of the rods to pass
through
6. Jacquards invention emphasized three
important concepts:
Storage: Coding of information by punching
holes on the cards.
Programming: Linking of the cards in series to
provide instruction in sequence.
Program Execution: Job would be performed
automatically as the program run.
7. Charles Babbage
1786 – J.H Muller proposed a
calculating machine called a Difference
Engine.
1812 – Charles Babbage conceived idea
of difference engine.
He designed new machine called
Analytical Engine.
8. Analytical Engine consisted of FIVE units.
Store: Storing the data.
Mill: Process the data.
Control: Control the flow of data.
Input: Enter the data.
Output: Display the data.
9. Babbage’s Analytical Engine could not
completed due to under development of
technology.
But laid foundation of digital computer.
Also called FATHER of computer.
10. Electro-Mechanical Machines
1890 Hollerith won competition for
developing data processing equipment
for the US Census Bureau.
Founded Hollerith Tabulating Company
which became IBM in 1924.
11. Computer Generations
Generation Technology Approx Dates
First Vacuum Tube 1942-1959
Second Transistors 1959-1964
Third ICs 1964-1973
SSI/MSI
Fourth Microprocessor 1973-1991
LSI/VLSI
Fifth ULSI/AI 1991 onwards
12. First Generation 1942-1959
First Generation Electronic
Computers used Vacuum Tubes.
Invented in 1906.
Vacuum tubes are glass tubes with
circuits inside.
Vacuum tubes have no air inside of
them, which protects the circuitry.
13. 1943 Work started on ENIAC at University of
Pennsylvania under John Mauchly and J.
Presper Eckert with Herman Goldstein.
Used 18,000 vacuum tubes.
U shaped, 25m long, 2.5m high, 1m wide,
consumed 150 kw and weighed more than
30 tons.
14. Disadvantages:
Very big in size
Slow in speed (40,000 operation in seconds)
Low reliability
Large power consumption
Difficult maintenance
15. Second Generation 1959-1964
Transistor was invented in 1948.
Made up of from Silicon.
A transistor is a semiconductor
device used to amplify and switch
electronic signals.
Replaced vacuum tubes with
Transistors.
16. Comparing with Transistors:
Immediate functioning, no time for heating
necessary.
Smaller and low weight.
Process up to 200,000 ois.
Less power consumption.
Low susceptibility to trouble and long lifetime
17. Third Generation 1964-1973
Third Generation Computers
used Integrated Circuits (chips).
Invented in 1947.
Integrated Circuits are
transistors, resistors, and
capacitors integrated together
into a single “chip”.
Replaced Transistor with ICs
18. Comparing with Transistors:
Very small in scale.
Cheaper than transistors.
More reliable.
Process up to 1000,000 ois.
19. Fourth Generation 1973-1991
It contains micro chip.
A small piece of semiconductor material
carrying many integrated circuits
(Transistors, resistors, and capacitors).
Very Large Scale Integrated.
4004 had 2,250 transistors
The first microprocessors emerged
in the early 1970s and were used
for electronic calculators, using
binary-coded decimal (BCD)
arithmetic on 4-bit words.
20. Fifth Generation 1991 onwards
It contains all best combination.
Getting smaller and smaller, but we are still
using microchip technology.
Ultra Large Scale Integrated circuits.
Giving computer the ability to think.
Artificial Intelligence and Expert systems.
