Lecture 2


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Lecture 2

  1. 1. IT 110: Lecture 2<br />Computers : A History<br />
  2. 2. "Computers in the future may weigh no more than 1.5 tons.“ - Popular Mechanics, 1949<br />"I think there is a world market for maybe five computers."- Thomas Watson, chairman of IBM, 1943<br />"There is no reason anyone would want a computer in their home."- Ken Olson, president, chairman and founder of DEC<br />Computers: Rapidly changing history<br />
  3. 3. Always a Need for Computers<br />Abacus<br />People have wanted to create machines to help them sort data<br />In Ancient Times, one device used was the Abacus – used for counting<br />Adoption of the Arabic numeral system around the world<br />
  4. 4. Al-Jazari<br />The Castle Clock<br />The "castle clock", an astronomical clock invented by Al-Jazari in 1206, is thought to be the earliest programmable analog computer. It displayed the zodiac, the solar and lunar orbits, a crescent moon-shaped pointer traveling across a gateway causing automatic doors to open every hour, and five robotic musicians who play music when struck by levers operated by a camshaft attached to a water wheel. The length of day and night could be re-programmed every day in order to account for the changing lengths of day and night throughout the year.<br />
  5. 5. Since the Middle Ages, a series of inventions came out in Europe in which people created mechanisms that performed computer functions<br />In 1642 Blaise Pascal invented the mechanical calculator<br />In 1801 a punch card system was created to operate a loom to automatically make detailed patterns in clothing <br />Creating Mechanical Computers<br />
  6. 6. In 1880 the US government did a census, and it took 9 years to finish adding up all the numbers<br />Herman Hollerith built a counting machine, which was used in the 1888 census <br />With his machine it took 6 weeks to the calculations<br />Hollerith and his friends decided to create a company to sell his machines: International Business Machines (IBM)<br />Example of the Changes it Could Do<br />
  7. 7. Vacuum Tubes<br />Vacuum Tube from the 1960s<br />Thomas Edison credited with inventing the Vacuum Tube in the 19th century <br />By the 20th century was being used in all kinds of electronic equipment like radios, televisions and the earliest computers<br />
  8. 8. Around 1940, large computers were being built, such as ENAIC and the Mark I<br />they could only solve one problem at a time<br />Input was based on punched cards and paper tape, and output was displayed on printouts<br />Were so big because they need thousands of vacuum tubes<br />Needed a lot of electricity and generated lots of heat, making them prone to breaking down<br />Giant Computers<br />
  9. 9. Two important inventions in the 1950s<br /> Integrated circuits (aka microchips)<br />Transistors<br />They made computers much smaller and more efficient<br />Since then, scientists are continually able to make these components smaller and more powerful<br />Allowed for the use of monitors and keyboards, and able to run more than one task at a time<br />New Inventions<br />
  10. 10. Computers and the Public<br />Spacewar, invented in 1962<br />Video games show what the capabilities of computers are to the general public<br />Personal computers – people can buy their own computers<br />
  11. 11. Microsoft<br />Staff photo from 1978<br />Started in 1975, Microsoft started creating software to run computers – Operating Systems, like DOS and Windows<br />Also created programs like Microsoft Word<br />$$$<br />
  12. 12. Apple Inc<br />established on April 1, 1976 by Steve Jobs to sell the Apple I personal computer kit<br />In 1984, launched its Macintosh personal computer<br />Company has had ups and downs in the 80s and 90s<br />In 2007, shifted emphasis to mobile electronic devices<br />