Introduction to computer science
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Introduction to computer science






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Introduction to computer science Introduction to computer science Presentation Transcript

  • Introduction to Computer Science
    Computer History
    Mr. Oei
    ICS 2O1
  • What is a computer?
    System unit (tower)
    CD-ROM /
    DVD-ROM Drive
    USB slots
  • com·put·er
    1) A person who makes calculations, esp. with a calculating machine
    2) A machine that calculates!
    Before we had the modern digital machines we possess today, computers started off as
    Analog Devices
  • Analog Computers
    What does analog mean?
    Relating to, or using, information represented by an ever-changing physical quantity
  • What were the first computational devices invented?
    The first devices we had were based on our hands and fingers!
  • The Salamis Tablet
    500 BC
    Ancient Babylonian counting board!
  • 1300 AD
    In more recent times, we’re used to seeing the evolved version of the counting board…
    The Chinese abacus!
    crazy japanese abacus students
    The Japanese abacus! (Soroban)
  • Mechanical Counting Machines
    pascaline short vid
    The Pascalineis a mechanical calculating deviceinvented by the French philosopher and mathematician Blaise Pascal in 1642.
  • Mechanical Counting Machines
    The Leibniz Wheelwas invented by the famous mathematician Leibniz in 1673.
    ( + , - , * , / )
  • Mechanical Counting Machines
    Punched Cards were used by the French weaver Joseph Jacquard in 1810. The cards carried weaving instructions for the looms, later this idea offered a great use for storing info.
  • Mechanical Counting Machines
    Babbage’s Difference Engines were calculating machines made by Charles Babbage to produce tables of numbers that would be used by ship’s navigators.
  • Charles Babbage
    Difference engine was among the FIRST mechanical computers
    Babbage was tired of having humans “compute” calculations… and make mistakes
    Although it was extremely big, the basic architecture of it was very similar to a modern computer!
    composed of around:
    • 25,000 parts,
    • weighed fifteen tons (13,600 kg),
    • 8 ft (2.4 m) tall
    How big was it??
  • Charles Babbage
    This device had mechanical problems similar to those that Pascal and Leibniz had, and was not completed until 1991 by the London Science Museum.
    Babbage did not give up –went on to make a more general purpose, and complex machine…
  • The Analytical Engine
    • Combined Jaquard’s punch-card technology in order to pre-program commands
    babbage difference engine #2
    demo of difference engine
    Employs many of the features that modern day computers possess!
  • Electrical Counting Machines & Herman Hollerith
    The US census of the 1880 took 9 years to compile and led to inaccurate figures. To solve the problem, Herman Hollerith invented three things
    1) Machine readable media (through the use of punched cards)
    2) A tabulator to process these punched cards
    3) Key punch machine to make the cards
  • IBM
    • Hollerith’s machine was immensely successful. The general count of the population, then 63 million, took only 6 weeks to calculate!
    • Based on the success of his invention, Herman Hollerith and some friends formed a company that sold his invention all over the world. The company eventually became known as:
    International Business Machines
  • Electrical Counting Machines
    51 feet long and weighed over 5 tons
    MARK I was built by a team from IBM and Harvard University. Mark I used mechanical telephone switches to store information. It accepted data on punched cards, processed and then output the new data.
    Was also used to control weapons during the war!
  • A summary of analog computers
    Truly parallel - Therefore can perform multiple calculations at the same time
    Strength in calculating mathematical, physical and technical problems through the interaction of continuously varying (or dynamic) physical quantities or measures
    Used mechanical, electrical, and hydraulic means to perform calculations
    ex. speedometers, simulating weather patterns, analyzing hydraulic networks
  • Electronic Counting Machines
    By 1950, IBM had become ubiquitous in industry and government!
    Then came
    the ENIAC !!
    The first US-built all-electronic computer built to perform ballistics calculations. (Away from IBM)
  • Electronic Counting Machines
    * It was 1000X faster than Mark I, but drew a lot of power …even dimmed the lights of Philadelphia when switched on!!
    * Mark I: 5 Additions / sec.
    * ENIAC: 5,000 Additions / sec.
    * ENIAC was made of 18,000 vacuum tubes.
  • Electronic Counting Machines
    ENIAC’s Problems:
    1- short life of vacuum tubes
    2- It runs a single program, which means rewiring by a group of technicians is needed to change the program!!!
    Solution: the same group of researchers worked on another version of ENIAC that stored programs on punched cards
  • Transitioning into the era of modern computing
  • Computers and society
    In what two ways/areas did computers significantly impact World War II and how did computers help?