7GENERATIONS OF COMPUTERS First Generation( )Second Generation( )Third Generation( )Fourth Generation(1971- present)Vacuum TubesTransistorsIntegrated CircuitsMicroprocessorsBig and ClumsyHigh electricity consumptionLarger AC units were neededLot of electricity failure occurred.Smaller transistors were usedCore memory was developed.Faster than first generation computersIntegrated circuits developedPower consumption was low.100 times faster than the second generationDevelopment of portable computersFloppy disks, optical disks then flash memory became the popular storage media
10Super ComputerSupercomputers – are the largest, fastest and most powerful computers at present.
11Mainframe ComputersMainframe – these computers are very expensive and can handle more than hundred users at a time. They are found in large organization such as banks.
12Mini ComputersThese become outdated and are rarely used today. They were very popular in the 1960s. They take up less space, may fit on a desk or take up the space of filing cabinet. Modern versions would be something like servers
13MicrocomputerThis type of computer includes those for general purpose and for business needs. They are usually called PC’s (Personal Computers) based on the microprocessor.
14Types of Computers MICROCOMPUTER MINICOMPUTER MAINFRAME SUPERCOMPUTER Desktop, laptop, palmtopAbout the size of a small filing cabinetLarge office desk dimensionsRoomful of large filing cabinetsSIZE110-100500-thousandsUSERSMicrosecondsUnder 100 nanosecondsUnder 70 nanosecondsUnder 15 nanosecondsSPEEDJoysticks, modems, keyboard, printer, disk drives, monitor, etc.Terminals, printersMagnetic tape driveSpecial high-performance devicesPERIPHERALSDust-free, anti-virus, disk protectionAir- conditioning and security recommendedSpecial cooling, fire protection, security requiredENVIRONMENTCheapestSmall businesses or departments use itOften used as part of a network in medium to large businesses, e.g. banksSevere heat buildup, for superior (scientific) applicationsNOTES