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DefinitionDefinition

Computer - An electronic device that has Computer - An electronic device that has the ability to store, retrieve, and process the ability to store, retrieve, and process data and can be programmed with data and can be programmed with instructions that it remembers.instructions that it remembers.

Gross AnatomyGross Anatomy

HardwareHardware Equipment associated with the computerEquipment associated with the computer

• Input devices, processor, output devices, storageInput devices, processor, output devices, storage

SoftwareSoftware Instructions that tell the hardware what to doInstructions that tell the hardware what to do Two categories of software:Two categories of software:

• System softwareSystem software• Application softwareApplication software

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History of ComputersHistory of Computers

Modern computers result from Modern computers result from 2 streams of evolution 2 streams of evolution

Mechanization of arithmeticMechanization of arithmetic calculating machines calculating machines

(hardware)(hardware) Concept of stored programsConcept of stored programs

process control (software)process control (software)

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A Brief History of the ComputerA Brief History of the Computer

First “computer”?First “computer”? The first actual calculating mechanism known The first actual calculating mechanism known

to us is the to us is the abacus, which was invented about , which was invented about 2000 years ago2000 years ago

Abacus: The art of calculating with beadsAdapted From: http://www.maxmon.com/history.htm

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A Brief History of the ComputerA Brief History of the Computer

Many references cite the French Many references cite the French mathematician, physicist, and mathematician, physicist, and theologian theologian Blaise Pascal as being as being the inventor of the first mechanical the inventor of the first mechanical calculator in 1642, the calculator in 1642, the Arithmetic Machine

Adapted From: http://www.maxmon.com/history.htmLiebniz calculatorLiebniz calculator

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A Brief History of the ComputerA Brief History of the Computer

However, it now appears that the first mechanical However, it now appears that the first mechanical calculator may have been conceived by calculator may have been conceived by someone else almost 150 years earlier than someone else almost 150 years earlier than Pascal's machine. Can you guess who?Pascal's machine. Can you guess who?

Leonardo Da VinciLeonardo Da Vinci

Adapted From: http://www.maxmon.com/history.htm

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A Brief History of the ComputerA Brief History of the Computer

In the early 1800s, a French silk weaver called In the early 1800s, a French silk weaver called Joseph-Marie JacquardJoseph-Marie Jacquard invented a way of invented a way of automatically controlling the warp and weft automatically controlling the warp and weft threads on a silk loom by recording patterns of threads on a silk loom by recording patterns of holes in a string of cards holes in a string of cards

Adapted From: http://www.maxmon.com/history.htm

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A Brief History of the ComputerA Brief History of the Computer

The first device that might be considered The first device that might be considered to be a computer in the modern sense of to be a computer in the modern sense of the word was the Difference Engine to the word was the Difference Engine to automatically calculate mathematical automatically calculate mathematical tables conceived in 1822 by the British tables conceived in 1822 by the British mathematician and inventor mathematician and inventor Charles Charles BabbageBabbage

Adapted From: http://www.maxmon.com/history.htm

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A Brief History of the ComputerA Brief History of the Computer

The Difference Engine was only partially The Difference Engine was only partially completed when Babbage conceived the completed when Babbage conceived the idea of another, more sophisticated idea of another, more sophisticated machine called the Analytical Engine machine called the Analytical Engine

The Analytical Engine was intended to use The Analytical Engine was intended to use loops of Jacquard's punched cards to loops of Jacquard's punched cards to control an automatic calculator, which control an automatic calculator, which could make decisions based on the results could make decisions based on the results of previous computationsof previous computations

Adapted From: http://www.maxmon.com/history.htm

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A Brief History of the ComputerA Brief History of the Computer

Working with Babbage was Working with Babbage was Augusta Ada Augusta Ada LovelaceLovelace, the daughter of the English poet , the daughter of the English poet Lord Lord ByronByron. Ada, who was a splendid mathematician . Ada, who was a splendid mathematician and one of the few people who fully understood and one of the few people who fully understood Babbage's vision, created a program for the Babbage's vision, created a program for the Analytical EngineAnalytical Engine

Ada is now credited as being the first computer Ada is now credited as being the first computer programmer and, in 1979, a modern programmer and, in 1979, a modern programming language was named programming language was named ADAADA in her in her honourhonour

Adapted From: http://www.maxmon.com/history.htm

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A Brief History of the ComputerA Brief History of the Computer

In 1939, a German engineer, Konrad Zuse built the first programmable, general-purpose digital computer. His computer was built from electric relays to automate engineering calculations

“I was too lazy to calculate and so I invented the computer.”

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A Brief History of the ComputerA Brief History of the Computer

John Atanasoff invented the Atanasoff-Berry Computer (ABC) —the first electronic digital computer. Built in 1939, this computer used vacuum tubes and was based on binary arithmetic. It was never a fully operational product.

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A Brief History of the ComputerA Brief History of the Computer

In 1944, Howard Aiken completed the Mark I, the largest electromechanical calculator ever built. It was built with electromechanical relays and followed instructions punched in paper tape

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A Brief History of the ComputerA Brief History of the Computer

In 1945, Mauchly and Eckert built the ENIAC (Electronic Numerical Integrator and Computer). The ENIAC was built with 18,000 vacuum tubes that failed on an average of once every seven minutes

After the war, they created the UNIVAC I - the first general-purpose commercial computer

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First-Generation ComputersFirst-Generation Computers

1930s – 1940s1930s – 1940s Vacuum tubes used as switchesVacuum tubes used as switches Large computersLarge computers Extremely slow by today’s standardsExtremely slow by today’s standards Prone to frequent failureProne to frequent failure Includes the ABC, Mark I, ENIAC, UNIVAC,Includes the ABC, Mark I, ENIAC, UNIVAC,

and others of similar designand others of similar design

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Second-Generation Second-Generation ComputersComputers

1950s – mid-1960s1950s – mid-1960s Transistors used as switchesTransistors used as switches Smaller than vacuum-tube-built computersSmaller than vacuum-tube-built computers As much as a thousand times faster than As much as a thousand times faster than

first-generation computersfirst-generation computers More reliable and less expensiveMore reliable and less expensive

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Third-Generation ComputersThird-Generation Computers

Late 1960sLate 1960s Hundreds of transistors packed into a single Hundreds of transistors packed into a single

integrated circuit on a silicon chipintegrated circuit on a silicon chip Dramatic reduction in size and costDramatic reduction in size and cost Significant increases in reliability, speed, Significant increases in reliability, speed,

and efficiencyand efficiency Mass production techniques to manufacture Mass production techniques to manufacture

chips inexpensivelychips inexpensively

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Fourth-Generation ComputersFourth-Generation Computers

1970s to present1970s to present

Complete computer on a Complete computer on a chipchip

Radical change in the Radical change in the appearance, capability appearance, capability and availability of and availability of computerscomputers

Some LinksSome Links Computer History Computer History  http://www.youtube.com/watch?v=LvKxJ3bQRKE&feature=relatedhttp://www.youtube.com/watch?v=LvKxJ3bQRKE&feature=related Charles Babbage and His Difference EngineCharles Babbage and His Difference Engine http://www.youtube.com/user/ComputerHistory#p/u/69/KBuJqUfO4-http://www.youtube.com/user/ComputerHistory#p/u/69/KBuJqUfO4-

ww ENIACENIAC http://www.youtube.com/watch?v=wGIteTE9glQhttp://www.youtube.com/watch?v=wGIteTE9glQ Computer History Museum OverviewComputer History Museum Overview http://www.youtube.com/user/ComputerHistory#p/u/106/z6zeq-http://www.youtube.com/user/ComputerHistory#p/u/106/z6zeq-

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