1. Computer History CS 110 Fall 2005

2. Homework TA Office hours TA Office hours Sunday, Sept 4 th from 3-5Sunday, Sept 4 th from 3-5 Thornton Hall Stacks Computer LabThornton Hall Stacks Computer Lab

3. Review of HTML / Homedir Connect using Homedir Connect using Homedir Explain the parallel between public_html on Homedir (as observed using Windows Explorer) and www.people.virginia.edu (as observed using Internet Explorer) Explain the parallel between public_html on Homedir (as observed using Windows Explorer) and www.people.virginia.edu (as observed using Internet Explorer)www.people.virginia.edu Visit http://www.people.virginia.edu/~dcb8j Visit http://www.people.virginia.edu/~dcb8jhttp://www.people.virginia.edu/~dcb8j This page is found in my public_html folderThis page is found in my public_html folder Note the default is to display index.htmNote the default is to display index.htm Demonstrate IP/URL parallels Demonstrate IP/URL parallels http:// http://128.143.22.98/~dcb8j To find IP address, use http://www.dnsstuff.com/To find IP address, use http://www.dnsstuff.com/ Demonstrate subdirectories Demonstrate subdirectories http://www.people.virginia.edu/~dcb8j/Daughterhttp://www.people.virginia.edu/~dcb8j/Daughterhttp://www.people.virginia.edu/~dcb8j/Daughter Note the link to an image (Rotunda) on the webNote the link to an image (Rotunda) on the web Demonstrate access to specific web page (not default index.htm) Demonstrate access to specific web page (not default index.htm) http://www.people.virginia.edu/~dcb8j/Daughter/keene2.htmhttp://www.people.virginia.edu/~dcb8j/Daughter/keene2.htmhttp://www.people.virginia.edu/~dcb8j/Daughter/keene2.htm Note the reference to an image stored in a folder other than the folder in which the web page is found (“..” indicates the image is found in the parent folder)Note the reference to an image stored in a folder other than the folder in which the web page is found (“..” indicates the image is found in the parent folder) http://128.143.22.98/

4. What is a computer? Babbage’s “Difference Engine” for computing polynomials (1822) http://en.wikipedia.org/wiki/Difference_engine

5. Mechanical Calculators 1623 – first mechanical calculators 1623 – first mechanical calculators Add, subtract, multiply, divideAdd, subtract, multiply, divide 1800s – computers that are powered by steam and programmed by punch cards 1800s – computers that are powered by steam and programmed by punch cards Babbage and Ada Lovelace (Lord Byron’s daughter)Babbage and Ada Lovelace (Lord Byron’s daughter) IBM’s roots in 1890 censusIBM’s roots in 1890 census

6. Analog Computers 1900s - use a continuously variable physical quantity to store values 1900s - use a continuously variable physical quantity to store values Require “plumbing” to be adapted to new problems Require “plumbing” to be adapted to new problems The Soviet Water Integrator (1936) http://en.wikipedia.org/wiki/

7. Digital Computers 1940s – WW II 1940s – WW II Electronic circuits, vacuum tubes, etc.Electronic circuits, vacuum tubes, etc. Mercury tube and TV tube memoryMercury tube and TV tube memory Computer control over telephone linesComputer control over telephone lines Parallel developments in Germany, England, and the US Parallel developments in Germany, England, and the US

8. The British War Effort Colossus Colossus Crack German encryption codesCrack German encryption codes Made Normandy a success (18,000 messages per day)Made Normandy a success (18,000 messages per day) Churchill ordered it to be destroyed “in pieces no larger than a man’s hand”Churchill ordered it to be destroyed “in pieces no larger than a man’s hand” Colossus (1944) http://en.wikipedia.org/wiki/Image:Colossus.jpg

9. Alan Turing The creator of Colossus The creator of Colossus The father of modern computer science The father of modern computer science The inventor of the Turing Test The inventor of the Turing Test The discoverer of computability through the Turing Machine The discoverer of computability through the Turing Machine “Outed” as a homosexual in 1952 and forced to undergo hormone therapy “Outed” as a homosexual in 1952 and forced to undergo hormone therapy Committed suicide in 1954 Committed suicide in 1954

10. The US War Effort ENIAC ENIAC Used for Army ballisticsUsed for Army ballistics The first computer known to be completely generalizable (Turing Complete) The first computer known to be completely generalizable (Turing Complete)

11. The German War Effort Zuse Zuse Turing-Complete computerTuring-Complete computer Switched numeric representation from decimal system to binarySwitched numeric representation from decimal system to binary Utilized Von Neumann architecture where program is stored in same place as dataUtilized Von Neumann architecture where program is stored in same place as data First high-level programming languageFirst high-level programming language

12. Transistors 1947 – Bell Labs 1947 – Bell Labs Electronic switches Electronic switches On the same order as printing press and the telephone On the same order as printing press and the telephone Present in nearly *all* electronic devices Present in nearly *all* electronic devices Desktop computers were possible Desktop computers were possible

13. Integrated Circuits 1956 –Texas Instruments and Fairchild Semiconductor 1956 –Texas Instruments and Fairchild Semiconductor Layers of semiconductors permit complex lattices of digital switches Layers of semiconductors permit complex lattices of digital switches Semiconductors change conductivity in response to light (CCDs) or electricity (ICs) Semiconductors change conductivity in response to light (CCDs) or electricity (ICs)

14. 1960 - 1980 Things moved quickly Things moved quickly Mainframe computer designs were adapted to the new hardware Mainframe computer designs were adapted to the new hardware New uses for computers were discovered (supercomputers) New uses for computers were discovered (supercomputers) Simplicity and affordability made computing available for home use Simplicity and affordability made computing available for home use

15. Home Computers 1974 – Intel 8080 IC 1974 – Intel 8080 IC 1975 – Altair is first mass-produced 1975 – Altair is first mass-produced 1977 – Apple II 1977 – Apple II 1981 – IBM PC 1981 – IBM PC 1982 – Commodore 64 1982 – Commodore 64 Specs: 64,000 bytes of RAM (vs 1 trillion) 5,000 Hz (vs 4,000,000 Hz) Specs: 64,000 bytes of RAM (vs 1 trillion) 5,000 Hz (vs 4,000,000 Hz) Commodore 64 (1944)

16. Home Computers Critical features Critical features Operating SystemsOperating Systems CP/M  Microsoft copied to create MS-DOS CP/M  Microsoft copied to create MS-DOS Kill AppsKill Apps MacWrite and MacPaint MacWrite and MacPaint People started to need computers People started to need computers

17. Home Computers Graphical User Interface (GUI) Graphical User Interface (GUI) Apple Lisa (1983)Apple Lisa (1983) Apple Macintosh (1984 Superbowl)Apple Macintosh (1984 Superbowl) Microsoft Windows (1985)Microsoft Windows (1985)

18. The Future The number of transistors incorporated in a chip will approximately double every 24 months The number of transistors incorporated in a chip will approximately double every 24 months Gordan Moore’s Law, 1965 ftp://download.intel.com/museum/Moores_Law/Printed_Materials/Moores_Law_Poster_Ltr.pdfs.jpg

19. The Future Graphics Cards Graphics Cards Surpassing Moore’s LawSurpassing Moore’s Law Much faster than CPUs (Why?)Much faster than CPUs (Why?) Frequently the most expensive part on a computer (Why?)Frequently the most expensive part on a computer (Why?) What are game consoles?What are game consoles?