am
🧠

History of Computing

Hardware

First Generation Hardware (1951-1959)

  • Vacuum tubes
    • Large
    • Not reliable
    • Lots of heat
  • Magnetic drum
    • Memory device that rotated under read/write head
    • When memory cell was under head, data could be read/written
    • Very manual
  • Card readers --> magnetic tape drives
    • Card readers that read holes punched in a card
    • Sequential auxiliary storage devices
    • Audio cassettes

Second Generation Hardware (1959-1965)

  • Transistor
    • Replaced vacuum tube
    • Fast, small, durable, cheap
    • Nobel prize was rewarded for invention
  • Magnetic cores
    • Replaced magnetic drums
    • Information is available instantly
    • CPU no longer has to wait for drum to get to proper place to read/write
  • Magnetic disks
    • Replaced magnetic tape
    • Data accessed directly
    • Faster because you can refer to location of data

Third Generation Hardware (1965-1971)

  • Integrated circuits
    • Replaced circuit boards
    • Smaller, cheaper, faster, more reliable
    • Solid silicon containing transistors and other components
    • Boards were printed
  • Transistors
    • Now used for memory construction
    • One transistor = one bit of information
  • Terminal
    • Input/output device with keyboard and screen
    • Direct access to computer + immediate response

Fourth Generation Hardware (1971-Present)

Software

First Generation Software (1951-1959)

  • Machine language
  • Assembly languages and translators
    • Programs written using mnemonics
    • Mnemonics get translated to machine code
  • Programmers split into two groups
    • Application programmers
    • Systems programmers

Second Generation Software (1959-1956)

Third Generation Software (1965-1971)

  • Systems software
  • Separation between users and hardware
    • Software is being written for general public

Fourth Generation Software (1971–1989)

  • Structured programming
  • New application software for users
    • Spreadsheets
    • Word processors
    • DBMS

Fifth Generation Software (1990-Present)

Computing as a Tool

Computing as a Discipline

  • What can be efficiently automated?
    • Four necessary skills:
      • Algorithmic thinking
        • Express problems in terms of step-by-step procedures
      • Representation
        • Store data in a way it can be process efficiently
      • Programming
        • Algorithmic thinking + Representation --> computer software
      • Design
        • Software that serves a purpose

Computer Science History