© Paradigm Publishing Inc. 1-1 Chapter 1 Our Digital World

© Paradigm Publishing Inc. 1-2 Presentation Overview Immersed in Digital Technology The Computer Advantage How Computers Work Computers and Computer Systems Components of a Computer System Categories of Computers

© Paradigm Publishing Inc. 1-3 Immersed in Digital Technology Digital –refers to an electronic signal that is processed, sent, and stored as bits –bits are represented by “on” and “off” states

© Paradigm Publishing Inc. 1-4 Immersed in Digital Technology How has digital technology infiltrated your daily life? – Computer technology powers HDTVs, VCRs, microwave ovens, watches, cell phones, and automobiles. – Embedded chips, computers, networks, and the Internet and WWW enable us to communicate globally.

© Paradigm Publishing Inc. 1-5 Immersed in Digital Technology Computerized devices have embedded computers to perform a few specific actions

© Paradigm Publishing Inc. 1-6 Immersed in Digital Technology A computer is an electronic device that – operates under a set of instructions – accepts data that user supplies – manipulates data according to a program – produces results – stores the results

© Paradigm Publishing Inc. 1-7 The Computer Advantage Speed –Computers operate with lightning-like speed. –PCs execute billions of program instructions in one second. –Supercomputers execute trillions of instructions per second, the kind of processing required to forecast the weather and monitor space shuttle flights.

© Paradigm Publishing Inc. 1-8 The Computer Advantage Accuracy –Computers are accurate when accurate programs and data are entered. –If inaccurate programs and/or data are entered (garbage in), the output will also be inaccurate (garbage out) – GIGO.

© Paradigm Publishing Inc. 1-9 The Computer Advantage Versatility –Families use computers for entertainment, communications, budgeting, online shopping, homework, playing games, and listening to music. –Universities, government agencies, hospitals, and scientific organizations conduct life- enhancing research using computers. –Banks conduct money transfers, account withdrawals, and payment of checks via computer.

© Paradigm Publishing Inc The Computer Advantage Versatility –Retailers process sales transactions and check availability of products. –Manufacturers manage their entire production, warehousing, and selling processes. –Schools keep records, conduct distance-learning classes, schedule events, and analyze budgets.

© Paradigm Publishing Inc The Computer Advantage Storage –Computers accept and store programs and data. –Users can access a program again and again to process different data. –Computers store huge amounts of data in tiny physical spaces.

© Paradigm Publishing Inc The Computer Advantage Communications –Networks using special equipment and programs allow computers to communicate with each other through telephone lines, cable connections, and satellites. –Users can exchange information over wireless networks using personal digital assistants (PDAs), notebook computers, cell phones, and pagers.

© Paradigm Publishing Inc The Computer Advantage Communications A local area network (LAN) is a network confined to a small geographic area, such as a building, factory, or college campus.

© Paradigm Publishing Inc The Computer Advantage Communications A wide area network (WAN) spans a large geographical area and might connect a company’s manufacturing plants dispersed throughout the United States.

© Paradigm Publishing Inc The Computer Advantage Communications The Internet is a worldwide network of large and small networks linked together via communications hardware, software, and media for the purpose of communicating and sharing information.

© Paradigm Publishing Inc The Computer Advantage Communications The Internet is used for various purposes, including – sending and receiving messages – researching information – buying and selling products and services – taking online college courses – accessing entertainment

© Paradigm Publishing Inc The Computer Advantage Communications –World Wide Web – a system of linked computer networks that allows users to move from one site to another by way of links on Web pages –Web page – an electronic document stored on a computer running on a Web site –Search engine – a software program that locates and retrieves requested information

© Paradigm Publishing Inc The Computer Advantage What advantages do computers offer? –Provide speed, versatility, storage, and communications –Widely used in homes, workplace, and society –Used to communicate, manage finances, analyze data, plan, research, and for hundreds of other purposes

© Paradigm Publishing Inc How Computers Work Types of data –Text data – letters, numbers, and special characters –Graphic data – photographs, charts, and drawings –Audio data – voice and music –Video data – moving pictures and images

© Paradigm Publishing Inc How Computers Work Combining types of data can improve the presentation quality of a message.

© Paradigm Publishing Inc How Computers Work During the information processing cycle, data is entered into a computer, processed, sent as output, and stored (if required for future use).

© Paradigm Publishing Inc Computers and Computer Systems A personal computer system includes: – System unit – Input devices – Output devices – Storage devices – Communications devices

© Paradigm Publishing Inc Components of a Computer System A personal computer system includes: – System unit – electronic components process data into information – Input devices – allow users to enter instructions, data, and commands into a computer; common input devices: –keyboard, mouse, microphone – Output devices – make information available to the user; common output devices: –display screens, printers

© Paradigm Publishing Inc Components of a Computer System A personal computer system includes: – Storage devices – provide for permanent storage of programs, data, and information – Communications devices – allow a user to exchange instructions, data, and information with other computer users

© Paradigm Publishing Inc Components of a Computer System What is the difference between a computer and a computer system? – A computer is the part of the system that processes the data into information. – A computer system includes the computer along with input, output, storage, and communication devices.

© Paradigm Publishing Inc Categories of Computers Personal Computers –fits on a desk, in a briefcase, on a laptop, or is worn –executes 600 million to 3 billion instructions per second –used by a single user or as part of a network –costs a few hundred to thousands of dollars

© Paradigm Publishing Inc Categories of Computers Handheld Computer –fits in hand(s) or carried in a pocket –executes a few hundred instructions per second –used by a single user or as part of a network –costs $99 to a few hundred dollars

© Paradigm Publishing Inc Categories of Computers Workstation –similar in size to desktop PC but larger and more powerful –executes 3 to 5 billion instructions per second –used by a single user or as part of a network –costs a few thousand dollars

© Paradigm Publishing Inc Categories of Computers Midrange Server –fits into a large cabinet –executes billions of instructions per second –used by hundreds of users at the same time –costs $5,000 to hundreds of thousands of dollars

© Paradigm Publishing Inc Categories of Computers Large Server or Mainframe –occupies a partial or full room –executes billions of instructions per second –used by hundreds or thousands of users at the same time –costs several thousands to millions of dollars

© Paradigm Publishing Inc Categories of Computers Supercomputer –occupies a full room –executes trillions of instructions per second –used by thousands of users at the same time –costs several million dollars

© Paradigm Publishing Inc Categories of Computers What are the basic categories of computers and their distinguishing characteristics? – Personal computer – self-contained, capable of input, processing, output, and storage – Handheld computer – fits comfortably in a user’s hand – Workstation – high-performance single-user computer

© Paradigm Publishing Inc On the Horizon Based on the information presented in this chapter and your own experience, what do you think is on the horizon?