2. From Calculation to Communication Computer Currents: 1

3.  2001 Prentice Hall1.2 Chapter Outline Living without Computers Computers in Perspective: An Evolving Idea Computers Today: A Brief Taxonomy Computer Connections: The Internet Revolution Living with Computers “Consider the past and you shall know the future.” Chinese Proverb

4.  2001 Prentice Hall1.3 Do you realize the implications of computers in your every day life? Living Without Computers

5.  2001 Prentice Hall1.4 Information-Processing Machine Input documents Processing elements Print materials

6.  2001 Prentice Hall1.5 Howard Aiken John Atanasoff Inventors of the first real computers include: The First Real Computers Konrad Zuse John Mauchly & J. Presper Eckert

7.  2001 Prentice Hall1.6 “I was too lazy to calculate and so I invented the computer.” Zuse’s computer was built with electric relays and eventually vacuum tubes. Germany, 1939 Konrad Zuse

8.  2001 Prentice Hall1.7 Atanasoff-Berry Computer (ABC) This computer was built with vacuum tubes and based on binary arithmetic. It was never completed. John Atanasoff USA, 1939

9.  2001 Prentice Hall1.8 Howard Aiken USA, 1944 The Mark I was the largest electromechanical calculator ever built. It was built with electromechanical relays and followed instructions punched in paper tape.

10.  2001 Prentice Hall1.9 John Mauchly and Presper Eckert USA, 1945 Mauchly and Eckert built the ENIAC (Electronic Numerical Integrator and Computer). The ENIAC was built with vacuum tubes and programmed with plug wires and switches.

11.  2001 Prentice Hall1.10 Evolution and Acceleration First Generation –Vacuum tubes Second Generation –Transistors Third Generation –Integrated circuit Fourth Generation –Microprocessor

12.  2001 Prentice Hall1.11 First-Generation Computers 1930s – 1940s Vacuum tubes used as switches Large computers Extremely slow by today’s standards Prone to frequent failure Includes the ABC, Mark I, ENIAC, UNIVAC, and others of similar design

13.  2001 Prentice Hall1.12 Second-Generation Computers 1950s – mid-1960s Transistors used as switches Smaller than vacuum-tube-built computers As much as a thousand times faster than first-generation computers More reliable and less expensive

14.  2001 Prentice Hall1.13 Third-Generation Computers Late 1960s Silicon “chips” used as switches Dramatic reduction in size and cost Significant increases in reliability, speed, and efficiency

15.  2001 Prentice Hall1.14 Fourth-Generation Computers 1970s to present Switches of previous generations reduced to microprocessor Cost dropped so much that “hobbyists” could own them

16.  2001 Prentice Hall1.15 A Brief Taxonomy Mainframes Supercomputers Workstations Personal Computers Portable Computers Embedded Computer Special-Purpose Computers

17.  2001 Prentice Hall1.16 Multi-User Computers Supercomputers… the most powerful computers made

18.  2001 Prentice Hall1.17 Multi-User Computers Mainframes… allow several users access to the same computer Minicomputers… smaller and less expensive than mainframes

19.  2001 Prentice Hall1.18 Single-User Computers Workstations… the power of a minicomputer but less expensive.

20.  2001 Prentice Hall1.19 Single-User Computers Personal Computers (PC)… dedicated to serving one user

21.  2001 Prentice Hall1.20 Portable Computers Laptop –computers with flat screens, that are battery- operated and lightweight Palmtop –computers that are pocket-sized; power is not lost over portability

22.  2001 Prentice Hall1.21 Special-Purpose Computers Special-Purpose… often attached to sensors to measure and/or control the physical environment Embedded… used to enhance consumer goods

23.  2001 Prentice Hall1.22 Computer Connections Local Area Networks (LAN) –designed to share resources –allow communication between users (usually in the same building) Wide Area Networks (WAN) –designed to share resources –allow communication around the globe

24.  2001 Prentice Hall1.23 The Internet Explosion A network of networks Immense source of information Electronic mail Audio/Video links Multimedia simulations On-line transactions World Wide Web

25.  2001 Prentice Hall1.24 Electronic Mail (e-mail) Why did E-mail lure people to the Internet? –Availability software made it easy to use –Speed messages can be created and delivered in minutes “The great success of the Internet is not technical, but its human impact.” Dave Clark

26.  2001 Prentice Hall1.25 World Wide Web Web browsers help locate information on the Web Information is stored on Web pages A group of Web pages make up a Web site

27.  2001 Prentice Hall1.26 World Wide Web Enter a Web page’s unique address (URL) to go to the Web page http://www.prenhall.com.beekman

28.  2001 Prentice Hall1.27 Click a hot link to jump to different Web pages World Wide Web

29.  2001 Prentice Hall1.28 The Internet Culture Why do people connect to the Internet? -To Find Information -To Research Material -To get instant answers

30.  2001 Prentice Hall1.29 The Internet Culture To shop Play Games Check Stocks

31.  2001 Prentice Hall1.30 Internet Growth 1994? 3 million people connected Today? Hundreds of millions The United States leads the world in Internet activity –Approximately 1/3 of U.S. households connected in 1999 –By 2003, twice that number is expected to be connected

32.  2001 Prentice Hall1.31 Impact of the Internet Companies are replacing mainframe and PC systems with Intranets –Private networks that allow people to transmit, share and store information Computers may be used mostly to access Intranets and the Internet –IBM, Sun and Hewlett Packard are developing computers to act as network terminals

33.  2001 Prentice Hall1.32 Connecting to the Internet Direct connection –One that’s hard wired through an organization Indirect connection –Telephone system Cable TV connection Wireless connection

34.  2001 Prentice Hall1.33 Living with Computers What do you really need to know about computers? Implications? Applications? Explanations?

35.  2001 Prentice Hall1.34 Clarifying Technology Learn basic concepts of hardwareand software

36.  2001 Prentice Hall1.35 Computers in Action –Word processing and desktop publishing –Spreadsheets and databases –Computer graphics, multimedia and hypermedia Learn about the variety of software available: –Telecommunication and networking –Artificial intelligence –General problem- solving –Programming languages

37.  2001 Prentice Hall1.36 –Threat to personal privacy –Hazards of high- tech crime Social and Ethical Issues Learn about the impact of computers on your life: –Risk of computer failures –Protecting intellectual property –Threat of automation –Dehumanization of work –Abuse of information

38.  2001 Prentice Hall1.37 –Blurring of reality –Evolution of intelligence –Emergence of bio-digital technology Social and Ethical Issues –Technology dependence (remember the Y2K bug?) –The Death of privacy “For better and for worse, we’ll be coexisting with computers till death do us part.” George Beekman