3.9

• Information Revolution

  New technological revolution propelled by advances in electronics, a branch of applied physics that finds ways to make electric signals perform useful purposes
• The Information Revolution has had far-reaching consequences, especially as innovations in communications and computing have transformed the way many people live and work
• Innovations in the Information Revolution

  • Personal computers
  • Fax machines
  • Cell phones
  • The Internet
  • Electronic mail
  • The World Wide Web
• These electronic developments have made information instantly accessible and as easy to communicate as the click of a mouse
• Terms like "click of a mouse", "log on", "download", "IM", "broadband", and "google it" have become part of everyday speech for many people
• Charles Babbage's Analytical Engine

  • Designed to carry out complex arithmetical calculations with speed and accuracy
  • First digital computer in basic principles
• Alan Turing's Turing Machine

  • Described a device that would perform enormously complex processes, beyond arithmetical calculations
  • Explained the complex mathematics behind the processes of modern-day computers, as well as the enormous potential of such machines
• ENIAC

  Electronic Numerical Indicator And Computer, a machine developed during World War II to predict the trajectory of rapid artillery shells
• ENIAC was a dazzling scientific achievement, but it was expensive, massive, and tricky, and while it could rapidly solve complex mathematical problems, it was just a fabulous adding machine
• Developing computers beyond ENIAC


  1. Telling a computer what to do and when to do it

  2. Programming a computer to perform a variety of tasks

  3. Replacing punch cards and other mechanical forms of storage with data stored in instantaneously accessible electronic form
• John von Neumann's ideas

  • Stored-program concept - electronically storing instructions in a computer to enable it to perform a variety of tasks in a given sequence
• Transistors

  • Tiny devices to control the flow of electric current
  • Compared to vacuum tubes, transistors were small, stable, and cooler in operation
  • Reduced the size of computers and other electronic devices, and decreased the amount of energy required to run them
  • Brought down the price
• Integrated circuits (ICs)

  • Compressed hundreds of thousands of transistors on a single microchip smaller than a fingernail
  • Made computers smaller and enabled many of the technologies of the Information Revolution
• By the 1960s, engineers at IBM were designing computers small enough to fit in an elevator, and the Apollo Space Program relied on some of the new machines
• PET computer

  Fairly compact computer for business use, stood for "Personal Electronic Transactor"
• Microcomputer kits

  Computers that hobbyists could assemble in their homes
• Compilers

  New programs that enabled people to program computers easily and quickly
• Tasks computers were programmed to perform

  • Tracking a company's sales figures
  • Guiding the Apollo 12 spacecraft safely to the moon and back
• Scientists and engineers worked with new productivity, relying on computers to do millions of calculations that could not have been made a generation before
• PCs - Personal Computers

  Small, practical computers for personal use
• Microsoft

  • Founded by Bill Gates and Paul Allen in 1976
  • Developed and licensed software like Microsoft BASIC to companies including IBM and Apple
• Apple Computer

  • Cofounded by Steve Jobs and Stephen Wozniak
  • Built the Apple I and Apple II computers in the 1970s
• IBM decided to enter the small computer market

  Hired Microsoft to provide the operating system for IBM's PCs
• IBM PCs and clones

  • Sold faster than IBM's own PCs
  • Ran Microsoft's operating system
• Microchips

  Able to perform close to 5 million operations per second, compared to ENIAC's 5,000
• Apple Macintosh

  • Introduced in 1984
  • Used a mouse and graphical user interface instead of command line
• Laptops

  Portable computers that weighed as little as 5 pounds by the early 1990s
• Computers rapidly spread throughout businesses, schools, government agencies, and the military
• As computers became more capable and affordable, many families began using them at home
• H.G. Wells' vision of a "World Brain"

  A network or depot to receive, sort, summarize, digest, clarify, and compare knowledge and ideas
• ARPANET

  • First steps taken in the 1960s to link computers in a network by J.C.R. Licklider
  • Allowed users to share files, programs, and computer resources
• Internet

  Interconnected network of networks that developed from ARPANET and other research networks
• Private companies like CompuServe, Prodigy, and America Online provided access to the Internet for businesses and individuals
• TCP/IP

  Key innovation that enabled different networks to communicate and work together on the Internet
• ARPANET

  Early network used for military purposes
• Development of the Internet

  1. University-based networks linked

  2. Standards established to allow networks to work together

  3. Personal computers increased demand for access

  4. Fiber optic cables used to transmit data at higher speeds
• The Internet is not run by any single government or company, but by a number of agencies and voluntary groups that cooperate to set standards and keep it free and open
• World Wide Web

  Interconnected system of computer files that allows data on the Internet to be presented as pages of text and images on a computer screen
• World Wide Web

  • Highly flexible
  • Easy to change
• URL

  Universal Resource Locator