Generations of Computers

Generations of ComputersFirst GenerationSecond GenerationThird GenerationFourth GenerationFifth Generation

Year(1940-1956)(1956-1963)(1964-1971)(1971-present)(Present & next)

Hardware usedVacuum tubes

Memory- magnetic drums

Input punched cards & paper tapes

Output - printoutsTransistors

Primary memory magnetic core technology

Secondary memory magnetic tapes & magnetic disks

Input punched cards

Output -printoutsIntegrated circuits

Input keyboard

Output monitorLSI & VLSI (Very Large Scale Integration) technology

Primary memory- Semiconductor memory

Secondary memory magnetic disksSLSI (Super Large Scale Integrated Chip)

Software usedInstructions were written in machine language (0s & 1s)Instructions in assembly language, Mnemonics High level language. BASIC, PASCAL, COBOL,

FORTRON

High level programming language

MS-DOS & MS-Windows

GUIArtificial Intelligence

Computation timeMillisecondsMicrosecondsNano secondsPico secondsLess than pico seconds

Physical appearanceEnormous in sizeComputer size is reducedQuite small compared to 2nd generationSmaller than previous generations

ExamplesENIAC

EDVAC

UNIVAC

PDP-8

IBM1401

CDC 1604PDP-11

IBM 370

Apple I & II

INTEL-400LIBM compatible.

PARAM

AdvantageVacuum tubes were the only electronic components available at that time..These computers could perform computations in milliseconds.

Small in size when compared to 1st generation computersBetter speed and reliability

Small in sizeMore reliabilityLess heat generatedComputational time is NanosecondsEasily portableLess power requiredCommercial production was easier and cheaper

They are much more smaller in sizeVery cheap Consumes less powerHave more reliabilityLess hardware failuresThey have larger storage memory

It consumes less power than its predecessorsMore user friendlySupports newer and powerful applications having large primary

storage capacityPrice range is affordableSupports parallel processing

LimitationsVery big in sizeOccupies large spaceProduces large amount of heatHigh power consumptionHigh costNon portableNeed constant maintenance

Need constant maintenanceNeed air-conditioningHigh costCommercial production was difficult.

Need air-conditioningHighly sophisticated technology required for the manufacturer of IC chips.

Highly sophisticated technology required for the manufacture of VLSI chips.