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From Calculation to Communication. 1. Computer Currents:. Chapter Outline. “Consider the past and you shall know the future.” Chinese Proverb. Living without Computers Computers in Perspective: An Evolving Idea Computers Today: A Brief Taxonomy
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From Calculation to Communication 1 Computer Currents:
Chapter Outline “Consider the past and you shall know the future.” Chinese Proverb • Living without Computers • Computers in Perspective: An Evolving Idea • Computers Today: A Brief Taxonomy • Computer Connections: The Internet Revolution • Living with Computers 2001 Prentice Hall
Living Without Computers Do you realize the implications of computers in your every day life? 2001 Prentice Hall
Input documents Processing elements Print materials Information-Processing Machine 2001 Prentice Hall
The First Real Computers Inventors of the first real computers include: Konrad Zuse John Atanasoff Howard Aiken John Mauchly & J. Presper Eckert 2001 Prentice Hall
Konrad Zuse Germany, 1939 “I was too lazy to calculate and so I invented the computer.” Zuse’s computer was built with electric relays and eventually vacuum tubes. 2001 Prentice Hall
John Atanasoff USA, 1939 Atanasoff-Berry Computer (ABC) This computer was builtwith vacuum tubes andbased on binary arithmetic. It was never completed. 2001 Prentice Hall
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. 2001 Prentice Hall
John Mauchlyand 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. 2001 Prentice Hall
Evolution and Acceleration • First Generation • Vacuum tubes • Second Generation • Transistors • Third Generation • Integrated circuit • Fourth Generation • Microprocessor 2001 Prentice Hall
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 2001 Prentice Hall
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 2001 Prentice Hall
Third-Generation Computers • Late 1960s • Silicon “chips” used as switches • Dramatic reduction in size and cost • Significant increases in reliability, speed, and efficiency 2001 Prentice Hall
Fourth-Generation Computers • 1970s to present • Switches of previous generations reduced to microprocessor • Cost dropped so much that “hobbyists” could own them 2001 Prentice Hall
A Brief Taxonomy • Mainframes • Supercomputers • Workstations • Personal Computers • Portable Computers • Embedded Computer • Special-Purpose Computers 2001 Prentice Hall
Multi-User Computers Supercomputers… the most powerful computers made 2001 Prentice Hall
Multi-User Computers Mainframes… allow several users access to the same computer • Minicomputers… • smaller and less expensive than mainframes 2001 Prentice Hall
Single-User Computers Workstations… the power of a minicomputer but less expensive. 2001 Prentice Hall
Single-User Computers Personal Computers (PC)… dedicated to serving one user 2001 Prentice Hall
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 2001 Prentice Hall
Special-Purpose Computers Special-Purpose… often attached to sensors to measure and/or control the physical environment Embedded… used to enhance consumer goods 2001 Prentice Hall
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 2001 Prentice Hall
The Internet Explosion • A network of networks • Immense source of information • Electronic mail • Audio/Video links • Multimedia simulations • On-line transactions • World Wide Web 2001 Prentice Hall
Electronic Mail (e-mail) “The great success of the Internet is not technical, but its human impact.” Dave Clark 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 2001 Prentice Hall
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 2001 Prentice Hall
World Wide Web Enter a Web page’s unique address (URL) to go to the Web page http://www.prenhall.com.beekman 2001 Prentice Hall
World Wide Web Click a hot link to jump to different Web pages 2001 Prentice Hall
The Internet Culture Why do people connect to the Internet? -To Find Information -To Research Material -To get instant answers 2001 Prentice Hall
The Internet Culture To shop Play Games Check Stocks 2001 Prentice Hall
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 2001 Prentice Hall
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 2001 Prentice Hall
Connecting to the Internet • Direct connection • One that’s hard wired through an organization • Indirect connection • Telephone system • Cable TV connection • Wireless connection 2001 Prentice Hall
Living with Computers • What do you really need to know about computers? • Explanations? • Applications? • Implications? 2001 Prentice Hall
Clarifying Technology Learn basic concepts of hardware and software 2001 Prentice Hall
Word processing anddesktop publishing Spreadsheets anddatabases Computer graphics,multimedia and hypermedia Telecommunication and networking Artificial intelligence General problem-solving Programming languages Computers in Action Learn about the variety of software available: 2001 Prentice Hall
Social and Ethical Issues • Threat to personal privacy • Hazards of high-tech crime Learn about the impact of computers on your life: • Risk of computer failures • Threat of automation • Dehumanization of work • Abuse of information • Protecting intellectualproperty 2001 Prentice Hall
Social and Ethical Issues “For better and for worse, we’ll be coexisting with computers till death do us part.” George Beekman • Blurring of reality • Evolution of intelligence • Emergence of bio-digital technology • Technology dependence (remember the Y2K bug?) • The Death of privacy 2001 Prentice Hall