A History of Information Technology and Systems: Part Two

D. The Electronic Age: 1940 - Present.

  1. First Tries.
  2. Eckert and Mauchly.
    1. The First High-Speed, General-Purpose Computer Using Vacuum Tubes:
      Electronic Numerical Integrator and Computer (ENIAC)

      The ENIAC team (Feb 14, 1946). Left to right: J. Presper Eckert, Jr.; John Grist Brainerd; Sam Feltman; Herman H. Goldstine; John W. Mauchly; Harold Pender; Major General G. L. Barnes; Colonel Paul N. Gillon.
      ENIAC team
      ENIAC - Electronic Numerical Integrator and Computer
      Rear view (note vacuum tubes).
      ENIAC (rear view)
      • Electronic Numerical Integrator and Computer (ENIAC)
        • 1946.
        • Used vacuum tubes (not mechanical devices) to do its calculations.
          • Hence, first electronic computer.
        • Developers John Mauchly, a physicist, and J. Prosper Eckert, an electrical engineer
          • The Moore School of Electrical Engineering at the University of Pennsylvania
        • Funded by the U.S. Army.
        • But it could not store its programs (its set of instructions)
    2. The First Stored-Program Computer(s)
      The Manchester University Mark I (prototype).
      Manchester University Mark I
      • Early 1940s, Mauchly and Eckert began to design the EDVAC - the Electronic Discreet Variable Computer.
      • John von Neumann's influential report in June 1945:
        • "The Report on the EDVAC"
      • British scientists used this report and outpaced the Americans.
        • Max Newman headed up the effort at Manchester University
          • Where the Manchester Mark I went into operation in June 1948--becoming the first stored-program computer.
        • Maurice Wilkes, a British scientist at Cambridge University, completed the EDSAC (Electronic Delay Storage Automatic Calculator) in 1949--two years before EDVAC was finished.
          • Thus, EDSAC became the first stored-program computer in general use (i.e., not a prototype).
    3. The First General-Purpose Computer for Commercial Use: Universal Automatic Computer (UNIVAC).
      UNIVAC publicity photo.
      UNIVAC publicity shot
      • Late 1940s, Eckert and Mauchly began the development of a computer called UNIVAC (Universal Automatic Computer)
        • Remington Rand.
        • First UNIVAC delivered to Census Bureau in 1951.
      • But, a machine called LEO (Lyons Electronic Office) went into action a few months before UNIVAC and became the world's first commercial computer.
  3. The Four Generations of Digital Computing.
    1. The First Generation (1951-1958).Vacuum tubes
      1. Vacuum tubes as their main logic elements.
      2. Punch cards to input and externally store data.
      3. Rotating magnetic drums for internal storage of data and programs
        • Programs written in
          • Machine language
          • Assembly language
            • Requires a compiler.
    2. The Second Generation (1959-1963).Transistors
      1. Vacuum tubes replaced by transistors as main logic element.
        • AT&T's Bell Laboratories, in the 1940s
        • Crystalline mineral materials called semiconductors could be used in the design of a device called a transistor
      2. Magnetic tape and disks began to replace punched cards as external storage devices.
      3. Magnetic cores (very small donut-shaped magnets that could be polarized in one of two directions to represent data) strung on wire within the computer became the primary internal storage technology.
        • High-level programming languages
          • E.g., FORTRAN and COBOL
    3. The Third Generation (1964-1979).
      Computer chipChip, one 1/100 of inch
      Typical mainframe computer set-up circa 1967
      1. Individual transistors were replaced by integrated circuits.
      2. Magnetic tape and disks completely replace punch cards as external storage devices.
      3. Magnetic core internal memories began to give way to a new form, metal oxide semiconductor (MOS) memory, which, like integrated circuits, used silicon-backed chips.
        • Operating systems
        • Advanced programming languages like BASIC developed.
          • Which is where Bill Gates and Microsoft got their start in 1975.
    4. The Fourth Generation (1979- Present).
      1. Large-scale and very large-scale integrated circuits (LSIs and VLSICs)
      2. Microprocessors that contained memory, logic, and control circuits (an entire CPU = Central Processing Unit) on a single chip.
        • Which allowed for home-use personal computers or PCs, like the Apple (II and Mac) and IBM PC.
          • Apple II released to public in 1977, by Stephen Wozniak and Steven Jobs.
            • Initially sold for $1,195 (without a monitor); had 16k RAM.
          • First Apple Mac released in 1984.
          • IBM PC introduced in 1981.
            • Debuts with MS-DOS (Microsoft Disk Operating System)
        • Fourth generation language software products
          • E.g., Visicalc, Lotus 1-2-3, dBase, Microsoft Word, and many others.
          • Graphical User Interfaces (GUI) for PCs arrive in early 1980s
            • MS Windows debuts in 1983, but is quite a clunker.
              MS Windows 1985
              • Windows wouldn't take off until version 3 was released in 1990
            • Apple's GUI (on the first Mac) debuts in 1984,
              Apple Mac 1984
              with a one-time only Super Bowl ad.
              Apple Super Bowl ad


  1. Kenneth C. Laudon, Carol Guercio Traver, Jane P. Laudon, Information Technology and Systems, Cambridge, MA: Course Technology, 1996.
  2. Stan Augarten, BIT By BIT: An Illustrated History of Computers (New York: Ticknor & Fields, 1984).
  3. R. Moreau, The Computer Comes of Age: The People, the Hardware, and the Software, translated by J. Howlett (Cambridge: MIT Press, 1984).
  4. Telephone History Web Site. http://www.cybercomm.net/~chuck/phones.html
  5. Microsoft Museum. http://www.microsoft.com/mscorp/museum/home.asp
  6. Philip B. Meggs, A History of Graphic Design, 2nd ed., New York: Van Nostrand Reinhold, 1992.

Last revised: May 25, 2000 11:13 AM
Comments: jbutler@ua.edu