4. History of Computing Technology

History of Computer Systems Computer systems evolution Hardware & circuitry Programming User interfaces Operating systems Networking

Focus of Computing Manufacturing Distribution Information The Customer 1900 – 1960 1960 – 1990 1990 – 2010 2010 – present Mainframe Personal comp. Network comp. Smart comp.

Evolution of Circuitry 1950s Vacuum tubes Machine language Early 1960s Transistors High level programs cheaper Mid 1960s – 1970s Integrated circuits Timesharing Mini-computers Mid 1970s – present VLSI & micro processors PC, GUI, LANs & Internet

Pre - 1947 1642 Blaise Pascal’s calculator 1674 Gottfried Leibniz’s mechanical calculator 1804 Joseph-Marie Jacquard’s loom Automatic programmable weaving machine using punched cards control 1822 Charles Babbage’s complex clockwork calculator solving equations and printing results 1890 Hollerith’s tabulating machine using punched cards 1938 Konrad Zuse programmable electronic calculator (Z1) Z3 first calculator capable of automatic operation 1943 Mark I (IBM & Harvard Univ.) Huge programmable electronic calculator using electro-mechanical relays 1946/7 ENIAC (Eckert J. & Mauchly J.) Programmable digital computer used mainly to solve math problems 30 seconds to computer trajectories Used 17 480 vacuum tubes POST 1946/7 Idea of STORED PROGRAM CONCEPT Beginning of generations of true computers

Generations of Computers I Characteristics Pros & Cons First (1940 - 1956) Input –punched cards Circuitry – vacuum tubes (limited) Storage – magnetic tapes for unlimited storage and magnetic drums Stored program concept Machine language Frequent failure of vacuum tubes (too much down time) Pros & cons of machine languages Second (1956 - 1963) Used transistors in place of vacuum tubes Input – punched cards Batch processing Printers, tape storage and disk storage Assembly language used & the conceptualisation of high-level language programming Also mainframes ( large expensive computer designed to meet all organisation’s computing needs) ASCII – character set Faster, smaller and more reliable computers Faster I/O devices Ran one job at a time (inconvenient) Time consuming and inefficient

Generations of Computers II Characteristics Pros & Cons Third (1964 to 1971) Timesharing Use of terminal access, control devices, video display, keyboard Integrated circuits (many transistors + electronic chips on a single silicon chip) Small/medium/large scale integrated circuits (SSI/MSI/LSI == 10-20/20-200/ 200-5000 transistors) Minicomputers (smaller than a mainframe) Open architectures (connect according to non-proprietary published standards) Mainly assembly language (though also few high level languages) Sophisticated I/O devices Magnetic core and solid states for storage Ran many jobs at a time (more efficient), reduce computational time Cheaper computers (1/4 of mainframe) Access from different terminals Unbundled software (not tied to hardware manufacturer Increase in programming languages Standardization Low maintenance costs More reliable

Generations of Computers III Characteristics Pros & Cons Fourth Generation (1971 – 2010) VLSI technology Microprocessors (holding entire CU and ALU) – avoiding costly redesign e.g. 4004  Intel 8080 Microcomputers (used microprocessors for their CPU) Computer assembly kits Compact hardware/computers Operating system (program that manages internal computer functions) First stage – command-line interface Second stage – graphical user interface Computer networking (hardware and standards, TCP/IP etc) Refined I/O devices Development of majority of high level languages Cheapest - Third party supply of accessory devices Growth in personal computing, open architectures and user –interface design Pros of GUI Pros & Cons of networking Improved speed, storage and reliability

Generations of computers IV Characteristics Pros & Cons Fifth Generation (2011 - present ) Super large scale integrated chips. Artificial intelligence. Image and graph recognition Ability to solve highly complex problem including decision making, logical reasoning. More than one CPU for faster processing speed (dual core, quad core etc) Parallel processing and superconductors Quantum computation and molecular and nanotechnology  Natural language processing Power of HUMAN INTELLIGENCE Machines capable of learning and self-organisation Advantages of limitless speed, storage, versatility