Presentation on theme: "HISTORY OF COMPUTERS (WHAT CAME BEFORE OUR MODERN TIME-SAVING DEVICES) By Miss Hall and Mrs. Batchelor, 2014."— Presentation transcript:
HISTORY OF COMPUTERS (WHAT CAME BEFORE OUR MODERN TIME-SAVING DEVICES) By Miss Hall and Mrs. Batchelor, 2014
INVENTORS OF PRE- COMPUTERS InventorsInventions (Machine) Ancient civilizations (e.g. Egyptians, Chinese)ABACUS, a manual calculating machine Blaise PascalPASCALINE, an accounting adding machine Gottfried LeibnezSTEPPED RECKONER, a calculating machine Joseph-Marie JacquardJACQUARD’S LOOM, an automatic cloth-weaver Herman HollerithTABULATING MACHINE, to tally census results Charles BabbageANALYTICAL ENGINE, DIFFERENCE ENGINE
PASCAL AND LEIBNIZ
HOLLERITH’S & BABBAGE’S MACHINES
GENERATIONS OF COMPUTERS First Generation ( ) Second Generation ( ) Third Generation ( ) Fourth Generation (1971- present) Vacuum TubesTransistorsIntegrated CircuitsMicroprocessors Big and Clumsy High electricity consumption Larger AC units were needed Lot of electricity failure occurred. Smaller transistors were used Core memory was developed. Faster than first generation computers Integrated circuits developed Power consumption was low. 100 times faster than the second generation Development of portable computers Floppy disks, optical disks then flash memory became the popular storage media
1 ST & 2 ND GENERATION
3 RD & 4 TH GENERATION
SUPER COMPUTER Supercomputers – are the largest, fastest and most powerful computers at present.
MAINFRAME COMPUTERS Mainframe – these computers are very expensive and can handle more than hundred users at a time. They are found in large organization such as banks.
MINI COMPUTERS These become outdated and are rarely used today.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
MICROCOMPUTER This type of computer includes those for general purpose and for business needs. They are usually called PC’s (Personal Computers) based on the microprocessor.
TYPES OF COMPUTERS MICROCOMPUTERMINICOMPUTERMAINFRAMESUPERCOMPUTER Desktop, laptop, palmtop About the size of a small filing cabinet Large office desk dimensions Roomful of large filing cabinets SIZE thousandsUSERS MicrosecondsUnder 100 nanosecondsUnder 70 nanosecondsUnder 15 nanosecondsSPEED Joysticks, modems, keyboard, printer, disk drives, monitor, etc. Terminals, printersMagnetic tape drive Special high-performance devices PERIPHERALS Dust-free, anti-virus, disk protection Air- conditioning and security recommended Special cooling, fire protection, security required ENVIRONMENT Cheapest Small businesses or departments use it Often used as part of a network in medium to large businesses, e.g. banks Severe heat buildup, for superior (scientific) applications NOTES