Computers - An Overview

Rita Ester

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What is a Computer ?

Electronic device Executes the instructions

of a program (stored in it‘s memory)

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What a Computer does?

Accepts input (=data) Processes data according to

a program (=instructions) Produces output

(=information) Stores results

in memory (RAM) or in storage devices

Allows communication with other computers

Information Processing Cycle

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Information Processing Cycle

Not shown here: • Communication with other computers

©

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Some Basic Terms

Hardware• the physical parts of the computer.

Software• the programs (instructions) that tell the computer what to

do.

Data• individual facts like first name, last name, street address,

city.

Information• data which has been put together into a useful form, like a

complete mailing address

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Why is a Computer Powerful? Speed

• billions of actions per second.

Reliability / Consistency

• highly reliable components

Accuracy

• Error free processing

Storage• keeps huge amounts of data

Communication• increases the power of one computer

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Source

http://www.jegsworks.com/Lessons/lesson1-2/lesson1-1.htm