# evolution of computer

A.P.Mohana priyaa

Abacus

Chinese invented calculating device called ABACUS

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Also known as “SOROBAN” perform addition and

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subtraction

Wooden rack holding two horizontal wires with beads

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strung on them.

Rules memorized by the user

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Regular arithmetic problems can be done

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NAPIER’S

DEVICE

John Napier a Scottish Mathematician

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Set of eleven animal bones later it was replaced by

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rod

Number marked on them,they placed side by side

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Products and quotients of large numbers could be

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obtained

SLIDE RULE

Robert Bissoker invent slide rule in 1632

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Popular computing device

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Perform all arithmetic & trigonometric function

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Final value can be straight away read on scale

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PASCAL’S CALCULATING MACHINE(PASCALINE)

Blaise Pascal a French mathematician developed

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mechanical calculating machine called Pascal’s calculating machine in 1642 A.D

First real desktop calculating device that could add and

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subtract.

Construct of set of toothed wheels or gears.

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Each wheel having 0 through 9.

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Arithmetic operation performed by turning these wheels.

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Concept still seen in conventional electric meter

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and taxi meter,

LEIBNITZ’S IMPROVED PASCAL MACHINE

Pascal machine perform only addition and subtraction

operation

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Pascal machine was improved in 1673,

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Introduced wheel could perform multiplication, division and

square root operation.

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PUNCHED CARD MACHINE

In 1801,french weaver Joseph mane jacquard invented first

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punched card machine,

Involved in designing clothes and making patterns and

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design on cloth,

Control textile looms , invented punched cards.

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Cards with holes were used to make attractive design on

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fiber,

Presence and absence of punched hole represented two

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states for raisers or lowers of wrap thread

CHARLES BABBAGE’S ENGINE.

Charles Babbage (1792-1871) made a machine

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called difference engine.

Evaluate accurate algebric expression and

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mathematical tasks up to 20 decimal places,

This machine is also called as Babbage's

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difference engine,

Later adopted by insurances companies for

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computing life tables.

Modified the device in 1833.

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Modified device is called Analytical engine.

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If had memory unit, operation arithmetic operators.

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Producers the o/p

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In punched card format.

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Parts and working principle of Analytical Engine

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similar to today computer.

Charles Babbage is called “Father of computer”

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HOLLERITHIS CARD READING

MACHINE

Dr.Herman Hollerith of U.S.A, working in U.S.A as

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census offices

Developed a card reading machine and used punched

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cards for tabulating and calculating data,

Data was being compiled and analyzed.

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MARK-I DIGITAL COMPUTER

All calculating machines are invented basically

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mechanical machine.

First electro-mechanical computer developed in 1937 by

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Howard aiken.

Used Hollerith's punched cards and principle of

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computer stated by Charles Babbage

Automatically perform a sequence of arithmetic

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operators.

Huge mechanical calculator which occupied several

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norms.

Inside several miles of electrical wires and electro

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mechanical relays and mechanical counter for arithmetic

calculations

FIRST ELECTRONICS COMPUTER (ABC)

Dr.Jhon atanasoff and clifford berrs developed first

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electronic computer.

It is called as ABC.

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Use vaccum tubes for storage , arithmetic and logical

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function.

Special purpose used to solve simultaneous equation.

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It could perform 500 addition or 350 multiplication in

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one second.

ELECTRONIC NUMERICAL INTEGRATOR AND

CALCULATOR(ENIAC)

Electronic computer,

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Developed by prof.presper Eckert and john mauchly.

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Produced in 1940 for U.S.army

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It...

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