COMPUTER TYPES CRITERIA OF CLASSIFICATION

Transforms informationabout stellar andplanetary positions intoinformation aboutimportant dates andevents (harvests, etc).
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COMPUTER TYPES CRITERIA OF CLASSIFICATION COMPUTER TYPES CRITERIA OF CLASSIFICATION HISTORY METHODS OF DEALING WITH DATA GENERATIONS MANUFACTURERS WIDELY ACCEPTED CLASSIFICATION TYPES OF COMPUTERS IN HISTORY• Pre-mechanical computers• Mechanical computers• Electronic computers• Optical computers• Biological computers Pre-mechanical computers• an example of a computer with no moving parts• transforms information about stellar and planetary positions into information about important dates and events (harvests, etc.) Stonehenge Mechanical computers early designs for more traditionalAbacus computers - based on mechanical techniques.Slide ruleElectronic computers Optical computers• current research in computer architecture includes much work on the design of computers which use light beams to perform computation; these machines should be smaller, faster and cooler than current electronic machines Biological computers• computers based on DNA: problems are encoded on strands of DNA which are mixed in solution and react to form DNA-coded answers COMPUTER TYPES CRITERIA OF CLASSIFICATIONHISTORYTWO BASIC KINDSGENERATIONSMANUFACTURERSWIDELY ACCEPTED CLASSIFICATION ANALOG COMPUTER1. Analog computers measure the continuous change in something – Current in a wire – Movement of the tide – Rate at which a wheel turns2. More complicated to build than digital computers3. Analog computers are very rare today DIGITAL COMPUTERS1. Use discrete numbers (whole digits) to control the electrical circuits2. Built of switches that are either on or off – Can not have values in-between 0 or 1 like the analog computer – 1 turns the switch on – 0 turns the switch off1. Almost all computers built today are digital computers COMPUTER TYPES CRITERIA OF CLASSIFICATIONHISTORYTWO BASIC KINDSGENERATIONSMANUFACTURERSWIDELY ACCEPTED CLASSIFICATION First Generation - Vacuum Tubes1. From 1946 to 1956 • did from 2,000 to 16,000 additions per second • Had main memory 100 bytes to 2 kilobytes2. Used vacuum tubes3. Very large machines • special rooms to house them with air conditioning • specially trained technicians to run & maintainSecond Generation - Transistors 1. From 1959 to around 1965 2. Smaller, faster, and more reliable  used transistors  6,000 to 3,000,000 operations/s  main memory 6 kilobytes to 1.3 megabytes  Contained in four cabinets about 6 feet high by 4 feet wide, each weighing 250 pounds 1. one-tenth the price of a 1st Generation 2. become common in larger businesses and universities Third Generation - Integrated Circuits1. Form 1965 to around 19722. Used integrated circuits – many transistors on one piece of silicon3. Smaller, faster, more reliable, and lower in price – Size of a stove or refrigerator, some can fit on desktops – Can do 100,000 to 400,000,000 operations per second – Cost about one-tenth the amount of second generation computers4. Computers become very common in medium to large businessesFourth Generation - Microprocessors1. From 1972 until now2. Used large scale to very large scale integrated circuits – Put more than one IC on a silicon chip – Can do more than one function1. smaller, faster, more reliable, and lower in price – Size of a television or much smaller – Can do 500,000 to 1,000,000,000 operations/second – Cost one-tenth, or less, the amount of third generation1. very common in homes and business Future Computer Generations1. Most likely the following will happen to computer technology – It will become lower in price – Computers will become smaller and faster – Computers will have larger memories and more storage space2. Computers will become an integral part of everyones life COMPUTER TYPES CRITERIA OF CLASSIFICATIONHISTORYTWO BASIC KINDSGENERATIONSMANUFACTURERSWIDELY ACCEPTED CLASSIFICATION COMPUTER TYPES CRITERIA OF CLASSIFICATIONHISTORYTWO BASIC KINDSGENERATIONMANUFACTURERWIDELY ACCEPTED CLASSIFICATION WIDELY ACCEPTED WAYS• SIZE (Early days): mainframe, minicomputer, microcomputer.• SIZE (Now): Floortop, Desktop, Laptop, Palmtop, Wearable.• POWER: Supercomputer, server, enterprise server (mainframe), mid-range server (minicomputer), PC. PC• computer designed for general use by a single person.• PCs were first known as microcomputers because they were a complete computer but built on a smaller scale than the huge systems in use by most businesses.