Computers: Tools for an Information Age Chapter 1 Computers: Tools for an Information Age

Objectives Describe the three fundamental characteristics of computers Describe at least four areas of society in which computers are used Identify the basic components of a computer system: input, processing, output, and storage

Objectives List some common input, output, and storage media Distinguish data from information Describe the significance of networking Explain the significance of the Internet Explain the various classifications of computers

Forging a Computer-Based Society Traditional Cornerstones of Economy: Land Labor Capital New Economic Element: Information

What Is Computer Literacy? Awareness Knowledge Interaction Awareness Becoming aware of the importance, versatility, and pervasiveness of computers in our society

Knowledge Interaction Learning what computers are and how they work Learning some technical jargon Interaction Knowing how to use computers for some simple applications

Fundamental Characteristics Speed Reliability Storage Capability By-products

Benefits of Computers Productivity Decision Making Cost Reduction Workers use computers to do their jobs faster and better Many processes can be more efficiently controlled by computers Decision Making Helps decision makers sort out financial, geographical, and logistical factors Cost Reduction Helps hold down costs of labor, energy and paperwork Return

Computer System Components Hardware Equipment associated with the system Software Instructions that tell the hardware what to do People Computer programmer: writes software User: purchases and uses software Often called end-user

Hardware: The Basic Components of a Computer What is a Computer? Four primary components: Input devices Processor Output devices Storage

What Is a Computer? A machine that can be programmed to accept data, process it into useful information, and store it away Data: raw facts representing people and events Information: data that is organized, meaningful, and useful Return

Input: What Goes In Input: the data put into the computer for processing Common input devices: Keyboard Mouse Scanner Return

Keyboard Most common input device Generates electrical signals which are translated into characters Return

Mouse Moves over a flat surface Movement of mouse ball causes corresponding movement of pointer on screen Return

Scanner Reads special letters, numbers, and symbols Wand reader, bar code reader often used in stores Flatbed and sheet-fed scanners scan pictures or printed documents Return

The Processor and Memory: Data Manipulation Also called central processing unit (CPU) Memory (primary storage) Closely related to, but distinct from processor Provides temporary storage Return

Primary Storage Used to temporarily hold data After it is retrieved from input device and before it is processed After it is processed and before it is released to output device Temporary (volatile) storage Data in memory lost if power is lost or program closed Return

The Processor Center of activity in the computer Consists of electronic circuits Interprets and executes program instructions Communicates with input, output, and storage devices Actually transforms data into information Return

Output: What Comes Out Output: the result produced by the CPU Common forms of output: text, numbers, graphics, and sounds Common output devices: Screen (monitor): can display text, numbers, photographs, even video, in full color Printer: produces printed reports as instructed by a program Return

Secondary Storage Provides long-term storage Common media Separate from memory Common media Magnetic disks Optical disks Magnetic tape Return

Magnetic Disks The most common storage media Diskette: 3.5” flexible diskette in plastic case Hard Disk: more storage capacity and faster access than diskette Return

Optical Disks Use a laser beam to read large volumes of data inexpensively CD-ROMs DVD-ROMs Return

Magnetic Tape Stores large amounts of data inexpensively Often used for system backup Return

Peripheral Devices All hardware devices attached to the computer Includes all input, output, and storage devices

Networking Network: a system that uses communications equipment to connect computers and their resources Common network tools: Local Area Network (LAN) Modem Electronic mail

Local Area Network Personal computers in an office are connected so users can communicate Users can operate computers independently Can share resources and exchange data Return

Modem A device that allows users to communicate with other computers over telephone lines Required when you don’t have a digital connection such as DSL or a cable modem Return

Electronic Mail (e-mail) Send and receive messages electronically Can send text, pictures, links to Web sites Can attach files for collaboration Messages stored in computer “mailbox” Return

The Internet The largest and most far-flung network Connects users worldwide Not actually a network, but a collection of thousands of networks

Getting Connected To access the Internet, connect to a server computer Server receives, processes, and transmits information Computers use a standard to communicate Need an Internet Service Provider (ISP)

Internet Service Providers The owner of a server computer Charges a fee for access to the Internet Fee can provide unlimited access or be based on usage Provides the user a means to connect to the server Once connected, you can connect to the Internet and all other server computers Return

Computer Protocols Provides a standard way to communicate with other computers Transmission Control Protocol/Internet Protocol (TCP/IP) used on the Internet Allows different types of computers to share data Return

Getting Around the Internet Began as a means for Department of Defense and its research institutions to share information Information was text-only Commands to navigate were obscure Now, much more visually based Use browser to explore the Internet World Wide Web

Browser Software that allows you to use a mouse to explore the Internet Click on screen text and/or graphics to move to different locations Most commonly used to explore the World Wide Web Return

The World Wide Web A subset of the Internet Actually, a standard for displaying and transmitting information Web site: a location on the Web Home page: the main page of a Web site Return

Classification of Computers Personal Computers Notebook Computers Handheld Computers Midrange Computers Mainframes Supercomputers

Personal Computers Desktop computers Also known as PCs, microcomputers, or home computers Broken down into three categories: Low-end computers Fully-powered personal computers Workstations Network computer Central processing unit and minimal memory Designed to be used on a network Sometimes called thin client Return

PC Categories Low-end computers Fully powered computers Workstations Fine for home users, word processing, simple games, Internet access Fully powered computers Good for heavy use of graphics, programming, or action-oriented games Workstations Very high-end computers used by engineers, financial traders, and graphic designers Return

Notebook Computers Small, lightweight computers Capabilities approach that of desktop computers Similar processing and memory Most have hard disk, and diskette or CD-ROM drive Typically more expensive than comparable desktop computers Return

Handheld Computers Personal Digital Assistant (PDA) Pocket PC Keeps track of appointments, contacts, etc. Accepts input with hand-held stylus Pocket PC Offers capabilities of PDAs, plus the ability to run stripped-down versions of software such as word processing and spreadsheets Return

Midrange Computers Multi-user computers designed to serve the needs of medium-sized organizations Hundreds or thousands of users connected Used for inventory, order-entry, and other company-wide applications Return

Mainframes Very large and powerful computers Capable of processing billions of instructions per second Capable of handling billions of characters of data Often used for applications with many users Reservations systems Large mail-order houses E-mail servers Return

Supercomputers The fastest and most powerful computers Capable of processing trillions of instructions per second Used for very sophisticated applications requiring mammoth data manipulation: Weather forecasting Weapons research Special effects for movies Return

Personal Computer System