evolution of computer

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 Ø

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