Discovering-Computers-Fundamentals- 1-27-27-54.pdf

Chapter One Introduction to Computers Objectives bj i After completing this chapter, you will be able to: 1 Explain why computer literacy is vital to success in today's world 6 Differentiate among types, sizes, and functions of computers in each of these categories: personal computers (desktop), 2 Describe the five components of a computer: input devices, output mobile computers and mobile devices, game consoles, servers, devices, system unit, storage devices, and communications devices mainframes, supercomputers, and embedded computers 3 Discuss the advantages and disadvantages that users experience when working with computers 7 Explain how home users, small office/home office users, mobile users, power users, and enterprise users each interact with computers 4 Discuss the uses of the Internet and World Wide Web 8 Discuss how society uses computers in education, finance, 5 Distinguish between system software and application software government, health care, science, publishing, travel, and manufacturing 2 Chapter 1 Introduction to Computers A World of Computers Computers are everywhere: at work, at school, and at home (Figure 1-1). Mobile devices, such as many cell phones, often are classified as computers. Computers are a primary means of local and global communication for billions of people. Employees correspond with clients, students with classmates and teachers, and family with friends and other family members. Through computers, society has instant access to information from around the globe. Local and national news, weather reports, sports scores, airline schedules, telephone directories, maps and directions, job listings, credit reports, and countless forms of educational material always are accessible. From the computer, you can make a telephone call, meet new friends, share photos and videos, share opinions, shop, book flights, file taxes, take a course, receive alerts, and automate your home. In the workplace, employees use computers to create correspondence such as e-mail messages, memos, and letters; manage calendars; calculate payroll; track inventory; and generate invoices. At school, teachers use computers to assist with classroom instruction. Students use computers to complete assignments and research. Instead of attending class on campus, some students take entire classes directly from their computer. Figure 1-1 People use all types and sizes of computers in their daily activities. Introduction to Computers Chapter 1 3 People also spend hours of leisure time using a computer. They play games, listen to music or radio broadcasts, watch or compose videos and movies, read books and magazines, share stories, research genealogy, retouch photos, and plan vacations. Many people believe that computer literacy is vital to success. Computer literacy, also known as digital literacy, involves having a current knowledge and understanding of computers and their uses. Because the requirements that determine computer literacy change as technology changes, you must keep up with these changes to remain computer literate. This book presents the knowledge you need to be computer literate today. As you read this first chapter, keep in mind it is an overview. Many of the terms and concepts introduced in this chapter will be discussed in more depth later in the book. What Is a Computer? A computer is an electronic device, operating under the control of instructions stored in its own memory, that can accept data, process the data according to specified rules, produce results, and store the results for future use. NPO 4 Chapter 1 Introduction to Computers Data and Information Computers process data into information. Data is a collection of unprocessed items, which can include text, numbers, images, audio, and video. Information conveys meaning and is useful to people. As shown in Figure 1-2, for example, computers process several data items to print information in the form of a cash register receipt. DATA INFORMATION Arrow Deli PROCESSES 10 Park Street Maple River, DE 20393 Computes each item’s total price by multiplying (734) 555-2939 the quantity ordered by the item price (i.e., 2 * 1.49 = 2.98). QTY ITEM TOTAL Organizes data. 2 Medium Sodas 2.98 Sums all item total prices to determine order total 1 Small Turkey Sub 3.49 1 Caesar Salad 4.49 due from customer (13.12). 1 Bag of Chips 0.99 Calculates change due to customer by subtracting 3 Cookies 1.17 the order total from amount received (20.00 - 13.12 = 6.88). Total Due 13.12 Amount Received 20.00 Change 6.88 Thank You! Figure 1-2 A computer processes data into information. In this simplified example, the item ordered, item price, quantity ordered, and amount received all represent data. The computer processes the data to produce the cash register receipt (information). Information Processing Cycle Computers process data (input) into information (output). Computers carry out processes using instructions, which are the steps that tell the computer how to perform a particular task. A col- lection of related instructions organized for a common purpose is referred to as software. A com- puter often holds data, information, and instructions in storage for future use. Some people refer to the series of input, process, output, and storage activities as the information processing cycle. Recently, communications also has become an essential element of the information processing cycle. The Components of a Computer A computer contains many electric, electronic, and mechanical components known as hardware. These components include input devices, output devices, a system unit, storage devices, and communications devices. Figure 1-3 shows some common computer hardware components. Input Devices An input device is any hardware component that allows you to enter data and instructions into a computer. Five widely used input devices are the keyboard, mouse, microphone, scanner, and Web cam (Figure 1-3). Introduction to Computers Chapter 1 5 A computer keyboard contains keys you press to enter data into the computer. A mouse is a small handheld device. With the mouse, you control movement of a small symbol on the screen, called the pointer, and you make selections from the screen. A microphone allows a user to speak into the computer. A scanner converts printed material (such as text and pictures) into a form the computer can use. A Web cam is a digital video camera that allows users to create movies or take pictures and store them on the computer instead of on tape or film. Output Devices An output device is any hardware component that conveys information to one or more people. Three commonly used output devices are a printer, a monitor, and speakers (Figure 1-3). A printer produces text and graphics on a physical medium such as paper. A monitor displays text, graphics, and videos on a screen. Speakers allow you to hear music, voice, and other audio (sounds). monitor (output device) printer optical disc drive (output device) (storage device) screen Web cam (input device) speakers (output device) hard disk drive (storage device) system unit (processor, memory, mouse and storage devices) keyboard (input device) (input device) scanner (input device) microphone (input device) USB flash drive (storage device) card reader/writer (storage device) external hard disk modem (storage device) (communications device) memory cards (storage device) Figure 1-3 Common computer hardware components include the keyboard, mouse, microphone, scanner, Web cam, printer, monitor, speakers, system unit, hard disk drive, external hard disk, optical disc drive(s), USB flash drive, card reader/writer, memory cards, and modem. 6 Chapter 1 Introduction to Computers System Unit The system unit is a case that contains electronic components of the computer that are used to process data (Figure 1-3 on the previous page). The circuitry of the system unit usually is part of or is connected to a circuit board called the motherboard. Two main components on the motherboard are the processor and memory. The processor, also called the CPU (central processing unit), is the electronic component that interprets and carries out the basic instructions that operate the computer. Memory consists of electronic components that store instructions waiting to be executed and data needed by those instructions. Most memory keeps data and instructions temporarily, which means its contents are erased when the computer is shut off. Storage Devices Storage holds data, instructions, and information for future use. For example, computers can store hundreds or millions of customer names and addresses. Storage holds these items permanently. A computer keeps data, instructions, and information on storage media. Examples of storage media are USB flash drives, hard disks, optical discs, and memory cards. A storage device records (writes) and/or retrieves (reads) items to and from storage media. Storage devices often function as a source of input because they transfer items from storage to memory. A USB flash drive is a portable storage device that is small and lightweight enough to be trans- ported on a keychain or in a pocket (Figure 1-3). The average USB flash drive can hold about 4 billion characters. A hard disk provides much greater storage capacity than a USB flash drive. The average hard disk can hold more than 320 billion characters. Hard disks are enclosed in an airtight, sealed case. Although some are portable, most are housed inside the system unit (Figure 1-4). Portable hard disks are either external or removable. An external hard disk is a separate, freestanding unit, whereas you insert and remove a removable hard disk from the computer or a device connected to the computer. An optical disc is a flat, round, portable metal disc with a plastic coating. CDs, DVDs, and Blu-ray Discs are three types of optical discs. A CD can hold from 650 million to 1 billion characters. Some DVDs can store two full-length movies or 17 billion characters (Figure 1-5). Blu-ray Discs can store about 46 hours of standard video, or 100 billion characters. Some mobile devices, such as digital cameras, use memory cards as the storage media. You can use a card reader/writer (Figure 1-3) to transfer stored items, such as digital photos, from the memory card to a computer or printer. Figure 1-4 Most hard disks are Figure 1-5 A DVD in a DVD drive. housed inside the system unit. Communications Devices A communications device is a hardware component that enables a computer to send (transmit) and receive data, instructions, and information to and from one or more computers or mobile devices. A widely used communications device is a modem (Figure 1-3). Introduction to Computers Chapter 1 7 Communications occur over cables, telephone lines, cellular radio networks, satellites, and other transmission media. Some transmission media, such as satellites and cellular radio networks, are wireless, which means they have no physical lines or wires. Advantages and Disadvantages of Using Computers Society has reaped many benefits from using computers. A user is anyone who communicates with a computer or utilizes the information it generates. Both business and home users can make well- informed decisions because they have instant access to information from anywhere in the world. Students, another type of user, have more tools to assist them in the learning process. Advantages of Using Computers The benefits from using computers are possible because computers have the advantages of speed, reliability, consistency, storage, and communications. Speed: When data, instructions, and information flow along electronic circuits in a computer, they travel at incredibly fast speeds. Many computers process billions or trillions of operations in a single second. Reliability: The electronic components in modern computers are dependable and reliable because they rarely break or fail. Consistency: Given the same input and processes, a computer will produce the same results — consistently. Computers generate error-free results, provided the input is correct and the instructions work. Storage: Computers store enormous amounts of data and make this data available for processing anytime it is needed. Communications: Most computers today can communicate with other computers, often wirelessly. Computers allow users to communicate with one another. Disadvantages of Using Computers Some disadvantages of computers relate to the violation of privacy, public safety, the impact on the labor force, health risks, and the impact on the environment. Violation of Privacy: In many instances, where personal and confidential records stored on computers were not protected properly, individuals have found their privacy violated and identities stolen. Public Safety: Adults, teens, and children around the world are using computers to share publicly their photos, videos, journals, music, and other personal information. Some of these unsuspecting, innocent computer users have fallen victim to crimes committed by dangerous strangers. Impact on Labor Force: Although computers have improved productivity and created an entire industry with hundreds of thousands of new jobs, the skills of millions of employees have been replaced by computers. Thus, it is crucial that workers keep their education up-to-date. A sepa- rate impact on the labor force is that some companies are outsourcing jobs to foreign countries instead of keeping their homeland labor force employed. Health Risks: Prolonged or improper computer use can lead to health injuries or disorders. Computer users can protect themselves from health risks through proper workplace design, good posture while at the computer, and appropriately spaced work breaks. Two behavioral health risks are computer addiction and technology overload. Computer addiction occurs when someone becomes obsessed with using a computer. Individuals suffering from technology overload feel distressed when deprived of computers and mobile devices. Impact on Environment: Computer manufacturing processes and computer waste are depleting Green Computing natural resources and polluting the environment. Green computing involves reducing the For more information, visit electricity consumed and environmental waste generated when using a computer. Strategies that scsite.com/dcf2011/ch1/ support green computing include recycling, regulating manufacturing processes, extending the weblink and then click life of computers, and immediately donating or properly disposing of replaced computers. Green Computing. 8 Chapter 1 Introduction to Computers QUIZ YOURSELF 1-1 Instructions: Find the true statement below. Then, rewrite the remaining false statements so that they are true. 1. A computer is a motorized device that processes output into input. 2. A storage device records (reads) and/or retrieves (writes) items to and from storage media. 3. An output device is any hardware component that allows you to enter data and instructions into a computer. 4. Computer literacy involves having a current knowledge and understanding of computers and their uses. 5. Three commonly used input devices are a printer, a monitor, and speakers. Quiz Yourself Online: To further check your knowledge of pages 2 through 7, visit scsite.com/dcf2011/ ch1/quiz and then click Objectives 1 – 3. Networks and the Internet A network is a collection of computers and devices connected together, often wirelessly, via communications devices and transmission media. When a computer connects to a network, it is online. Networks allow computers to share resources, such as hardware, software, data, and infor- mation. Sharing resources saves time and money. The Internet is a worldwide collection of networks that connects millions of businesses, govern- ment agencies, educational institutions, and individuals (Figure 1-6). More than one billion people around the world use the Internet daily for a variety of reasons, including the following: to com- municate with and meet other people; to conduct research and access a wealth of information and news; to shop for goods and services; to bank and invest; to participate in online training; to engage The Internet in entertaining activities, such as planning vacations, playing online games, listening to music, For more information, visit scsite.com/dcf2011/ch1/ watching or editing videos, and books and magazines; to share information, photos, and videos; to weblink and then click The download music and videos; and to access and interact with Web applications. Figure 1-7 shows Internet. examples in each of these areas. Figure 1-6 The Internet is the largest computer network, connecting millions of computers and devices around the world. Introduction to Computers Chapter 1 9 communicate research and access information shop bank and invest online training entertainment download videos share information Web application Figure 1-7 Home and business users access the Internet for a variety of reasons. 10 Chapter 1 Introduction to Computers People connect to the Internet to exchange information with others around the world. E-mail allows you to send and receive messages to and from other users (read Ethics & Issues 1-1 for a related discussion). With instant messaging, you can have a live conversation with another con- nected user. In a chat room, you can communicate with multiple users at the same time — much like a group discussion. You also can use the Internet to make a telephone call. Businesses, called access providers, offer access to the Internet free or for a fee. By subscribing to an access provider, you can use your computer and a modem to connect to the many services of the Internet. The Web, short for World Wide Web, is one of the more popular services on the Internet. The Web contains billions of documents called Web pages. A Web page can contain text, graphics, ani- mation, audio, and video. The nine screens shown in Figure 1-7 on the previous page are examples of Web pages. Web pages often have built-in connections, or links, to other documents, graphics, other Web pages, or Web sites. A Web site is a collection of related Web pages. Some Web sites allow users to access music and videos that can be downloaded, or transferred to storage media in a computer or portable media player. Once downloaded, you can listen to the music through speakers, headphones, or earbuds, or view the videos on a display device. Anyone can create a Web page and then make it available, or publish it, on the Internet for oth- ers to see. Millions of people worldwide join online communities, each called a social networking Web site or online social network, that encourage members to share their interests, ideas, stories, photos, music, and videos with other registered users. Hundreds of thousands of people today also use blogs to publish their thoughts on the Web. A blog is an informal Web site consisting of time- stamped articles in a diary or journal format, usually listed in reverse chronological order. As others read the articles in a blog, they reply with their own thoughts (to learn more about creating and using blogs, complete the Learn How To 1 activity on page 34). Podcasts are a popular way people verbally share information on the Web. A microblog, such as Twitter, allows users to publish short messages, usually between 100 and 200 characters, for others to read. A podcast is recorded audio stored on a Web site that can be downloaded to a computer or a portable media player such as an iPod. A Web application is a Web site that allows users to access and interact with software from any computer or device that is connected to the Internet. Examples of software available as Web applications include those that allow you to send and receive e-mail messages, prepare your taxes, organize digital photos, create documents, and play games. Web sites such as social networking Web sites, blogs, and Web applications are categorized as Web 2.0 sites. The term Web 2.0 refers to Web sites that provide a means for users to share personal information (such as social networking Web sites), allow users to modify the Web site contents (such as some blogs), and/or have software built into the site for users to access (such as Web applications). ETHICS & ISSUES 1-1 What Should Be Done about Identity Theft? Using e-mail and other techniques on to deter identity theft in several ways: bear the brunt of the problem by spending the Internet, scam artists are employing 1) shred your financial documents before hundreds of millions of dollars responding to a technique known as phishing to try to discarding them, 2) do not click links in complaints and finding and processing steal your personal information, such as unsolicited e-mail messages, and 3) enroll the criminals. credit card numbers, banking information, in a credit monitoring service. Consumer and passwords. For example, an e-mail advocates often blame credit card com- Who should be responsible for protecting message may appear to be a request from panies and credit bureaus for lax security the public from online identity theft? your bank to verify your Social Security standards. Meanwhile, the companies Why? Should laws be changed to stop number and online banking password. blame consumers for being too gullible it, or should consumers change behav- Instead, the information you submit ends and forthcoming with private informa- ior? What is an appropriate punish- up in the hands of the scammer, who tion. Both sides blame the government for ment for identity thieves? Given the then uses the information for a variety poor privacy laws and light punishments international nature of the Internet, of unethical and illegal acts. Sadly, the for identity thieves. But while the argu- how should foreign identity thieves be result often is identity theft. You can help ments go on, law enforcement agencies handled? Why? Introduction to Computers Chapter 1 11 FAQ 1-1 What U.S. Web sites are visited most frequently? Top U.S. Web Sites Number of Unique Monthly Visitors A recent survey found that Google’s Web site is visited most frequently, with Microsoft 160,000,000 and Yahoo! not far behind. The chart to the right shows the five most frequently visited 140,000,000 120,000,000 Web sites, as well as the approximate number of unique visitors per month. 100,000,000 For more information, visit scsite.com/dcf2011/ch1/faq and then click Top Web Sites. 80,000,000 60,000,000 An FAQ (frequently asked question) helps you find answers to commonly asked 40,000,000 questions. Web sites often post an FAQ section, and each chapter in this book 20,000,000 includes FAQ boxes related to topics in the text. 0 e. lin orp le t o! L of AO og ho os On C Go Ya icr ws M Ne Source: ClickZ Computer Software Software, also called a program, is a series of related instructions, orga- application nized for a common purpose, that icons software tells the computer what task(s) to perform and how to perform them. You interact with a program through its user interface. Software today often has a graphical user interface. With a graphical user interface (GUI pronounced gooey), you interact with the software using text, graphics, and visual images such as icons. An icon is a miniature image that represents a program, an instruc- tion, or some other object. You can use the mouse to select icons that system software perform operations such as starting a program. Figure 1-8 Today’s system software and application software usually have a graphical The two categories of software user interface. are system software and application software. Figure 1-8 shows an example of each of these categories of software, which are explained in the following sections. System Software System software consists of the programs that control or maintain the operations of the computer and its devices. System software serves as the interface between the user, the application software, and the computer’s hardware. Two types of system software are the operating system and utility programs. Operating System An operating system is a set of programs that coordinates all the activities among computer hardware devices. It provides a means for users to communicate with the computer Windows and other software. Many of today’s computers use Microsoft’s Windows, the latest version of which For more information, visit is shown in Figure 1-8, or Mac OS, Apple’s operating system. scsite.com/dcf2011/ch1/ When a user starts a computer, portions of the operating system are copied into memory from the weblink and then click computer’s hard disk. These parts of the operating system remain in memory while the computer is on. Windows. 12 Chapter 1 Introduction to Computers Utility Program A utility program allows a user to perform maintenance-type tasks usually related to managing a computer, its devices, or its programs. For example, you can use a utility program to transfer digital photos to an optical disc. Most operating systems include several utility programs for managing disk drives, printers, and other devices and media. You also can buy utility programs that allow you to perform additional computer management functions. Application Software Application software consists of programs designed to make users more productive and/or assist them with personal tasks. A widely used type of application software related to communications is a Web browser, which allows users with an Internet connection to access and view Web pages or access programs. Other popular application software includes word processing software, spreadsheet software, database software, and presentation software. Many other types of application software exist that enable users to perform a variety of tasks. These include personal information management, note taking, project management, accounting, document management, computer-aided design, desktop publishing, paint/image editing, audio and video editing, multimedia authoring, Web page authoring, personal finance, legal, tax preparation, home design/landscaping, travel and mapping, education, reference, and entertainment (e.g., games or simulations). Software is available at stores that sell computer products (Figure 1-9) and also online at many Web sites. Figure 1-9 Stores that sell computer products have shelves stocked with software for sale. Installing and Running Programs When purchasing software from a retailer, you typically receive a box that includes an optical disc(s) that contains the program. If you acquire software from a Web site on the Internet, you may be able to download the program; that is, the program transfers from the Web site to the hard disk in your computer. The instructions in software are placed on storage media, either locally or online. To use software that is stored locally, such as on a hard disk or optical disc, you usually need to install the software. Web applications that are stored online, by contrast, usually do not need to be installed. Installing is the process of setting up software to work with the computer, printer, and other hardware. When you buy a computer, it usually has some software preinstalled on its hard disk. This enables you to use the computer the first time you turn it on. To begin installing additional software from an optical disc, insert the program disc in an optical disc drive. To install downloaded software, the Web site typically provides instructions for how to install the program on your hard disk. Once installed, you can run the program. When you instruct the computer to run an installed pro- gram, the computer loads it, which means the program is copied from storage to memory. Once in memory, the computer can carry out, or execute, the instructions in the program so that you can use the program. Figure 1-10 illustrates the steps that occur when a user installs and runs a program. Introduction to Computers Chapter 1 13 Installing and Running a Computer Program Step 1: INSTALL Step 2: RUN When you insert a program disc, such as a photo Once installed, you can instruct the computer to editing program, in the optical disc drive for the run the program. The computer transfers instructions first time, the computer begins the procedure of from the hard disk to memory. installing the program on the hard disk. optical disc instructions transfer to memory Step 3: USE The program executes so that you can use it. This program enables you to edit photos. Figure 1-10 This figure shows how to install and run a computer program. Software Development A programmer, sometimes called a developer, is someone who develops software or writes the instructions that direct the computer to process data into information. Complex pro- grams can require thousands to millions of instructions. Programmers use a program- ming language or program development tool to create computer programs. Popular programming languages include C++, Visual C#, Visual Basic, JavaScript, and Java. Figure 1-11 shows a simple Visual Basic program. Figure 1-11 Some of the instructions in a program. 14 Chapter 1 Introduction to Computers QUIZ YOURSELF 1-2 Instructions: Find the true statement below. Then, rewrite the remaining false statements so that they are true. 1. A resource is a collection of computers and devices connected together via communications devices and transmission media. 2. Installing is the process of setting up software to work with the computer, printer, and other hardware. 3. Popular system software includes Web browsers, word processing software, spreadsheet software, database software, and presentation software. 4. The Internet is one of the more popular services on the Web. 5. Two types of application software are the operating system and utility programs. Quiz Yourself Online: To further check your knowledge of pages 8 through 13, visit scsite.com/ dcf2011/ch1/quiz and then click Objectives 4 – 5. Categories of Computers Industry experts typically classify computers in seven categories: personal computers (desktop), mobile computers and mobile devices, game consoles, servers, mainframes, supercomputers, and embedded computers. A computer’s size, speed, processing power, and price determine the category it best fits. Due to rapidly changing technology, however, the distinction among categories is not always clear- cut. This trend of computers and devices with technologies that overlap, called convergence, leads to computer manufacturers continually releasing newer models that include similar functionality and features. For example, newer cell phones often include media player, camera, and Web browsing capa- bilities. As devices converge, users need fewer devices for the functionality that they require. When consumers replace outdated computers and devices, they should dispose of them properly (read Ethics & Issues 1-2 for a related discussion). Figure 1-12 summarizes the seven categories of computers. The following pages discuss computers and devices that fall in each category. ETHICS & ISSUES 1-2 Should Recycling of Electronics Be Made Easier? Experts estimate that about one Some lawmakers prefer an set up recycling programs, many billion computers have been dis- aggressive approach, such as claim that forcing them to bear the carded to date. The discarded items setting up a recycling program cost of recycling programs puts the often are known as e-waste. As that would be paid for by add- company at a competitive disad- technology advances and prices fall, ing a $10 fee to the purchase vantage when compared to foreign many people think of computers, price of computers and computer companies that may not be forced cell phones, and portable media equipment, or forcing computer to maintain a recycling program. players as disposable items. These manufacturers to be responsible items often contain several toxic for collecting and recycling their Why is electronics recycling not as elements, including lead, mercury, products. California already requires popular as other types of recycling? and barium. Computers and mobile a recycling fee for any products How can companies make it easier devices thrown into landfills or sold that include certain electronic to recycle electronics while being burned in incinerators can pol- equipment. Manufacturers have compensated fairly for the cost lute the ground and the air. A vast taken steps, such as offering to of recycling? Should the govern- amount of e-waste ends up pol- recycle old computers and using ment, manufacturers, or users be luting third world countries. One energy efficient and environmentally responsible for recycling of obso- solution is to recycle old electronic friendly manufacturing techniques, lete equipment? Why? Should the equipment, but the recycling effort but some claim that consumers government mandate a recycling has made little progress especially should bear the responsibility of program for electronics? Why or when compared to recycling pro- disposing of their old computer why not? grams for paper, glass, and plastic. parts. While some companies have Introduction to Computers Chapter 1 15 Categories of Computers Number of Simultaneously Category Physical Size Connected Users General Price Range Personal computers (desktop) Fits on a desk Usually one (can be Several hundred to several thousand dollars more if networked) Mobile computers and Fits on your lap or in Usually one Less than a hundred dollars to several mobile devices your hand thousand dollars Game consoles Small box or handheld device One to several Several hundred dollars or less Servers Small cabinet Two to thousands Several hundred to a million dollars Mainframes Partial room to a full room Hundreds to thousands $300,000 to several million dollars of equipment Supercomputers Full room of equipment Hundreds to thousands $500,000 to several billion dollars Embedded computers Miniature Usually one Embedded in the price of the product Figure 1-12 This table summarizes some of the differences among the categories of computers. These should be considered general guidelines only because of rapid changes in technology. Personal Computers A personal computer is a computer that can perform all of its input, FAQ 1-2 processing, output, and storage activities by itself. A personal computer contains a processor, memory, and one or more input, output, and stor- Are PCs or Apple computers age devices. Personal computers also often contain a communications more popular? device. While PCs still are more popular than Apple Two popular architectures of personal computers are the PC computers, Apple computer sales have been ris- ing consistently during the past few years. In fact, (Figure 1-13) and the Apple (Figure 1-14). The term, PC-compatible, Apple computer sales now account for more than refers to any personal computer based on the original IBM per- 20 percent of all computer sales in the United sonal computer design. Companies such as Dell and Toshiba sell States, with that number estimated to grow for PC-compatible computers. PC and PC-compatible computers usually the foreseeable future. use a Windows operating system. Apple computers usually use a For more information, visit scsite.com/ Macintosh operating system (Mac OS). dcf2011/ch1/faq and then click Personal Two types of personal computers are desktop computers and Computer Sales. notebook computers. Figure 1-13 PC and PC-compatible computers usually use a Figure 1-14 Apple computers, such as the Windows operating system. iMac, usually use a Macintosh operating system. 16 Chapter 1 Introduction to Computers Desktop Computers A desktop computer is designed so that the system unit, input devices, output devices, and any other devices fit entirely on or under a desk or table. In some models, the monitor sits on top of the system unit, which is placed on the desk. The more popular style of system unit is the tall and narrow tower, which can sit on the floor vertically. Mobile Computers and Mobile Devices A mobile computer is a personal computer you can carry from place to place. Similarly, a mobile device is a computing device small enough to hold in your hand. The most popular type of mobile computer is the notebook computer. Notebook Computers display A notebook computer, also called a laptop computer, is a portable, personal computer often designed to fit on your lap. Notebook computers are thin and lightweight, yet can be as powerful as the average desktop computer. A netbook, which is a type of notebook computer, is smaller, lighter, and often not as powerful as a traditional notebook keyboard computer. Most netbooks cost less than traditional note- book computers, usually only a few hundred dollars. Some notebook computers have touch screens, allowing you to hinge interact with the device by touching the screen, usually with the tip of a finger. On a typical notebook computer, the keyboard is on top of the system unit, and the display attaches to the system unit with hinges (Figure 1-15). These computers weigh on average from 2.5 to more than 10 pounds (depending on Figure 1-15 configuration), which allows users easily to transport the optical On a typical notebook disc drive computers from place to place. Most notebook computers computer, the keyboard is on can operate on batteries or a power supply or both. top of the system unit, and the display attaches to the system unit with hinges. Tablet PCs Resembling a letter-sized slate, the Tablet PC is a special type of notebook computer that allows you to write or draw on the screen using a digital pen (Figure 1-16). For users who prefer typing instead of handwriting, you can attach a keyboard to Tablet PCs that do not include one already. Most Tablet PCs have touch screens. Tablet PCs are useful especially for taking notes in locations where the standard notebook computer is not practical. Mobile Devices Mobile devices, which are small enough to carry in a pocket, usually store programs and data permanently Figure 1-16 on memory inside the system unit or on small storage A Tablet PC combines media such as memory cards. You often can connect a the features of a traditional mobile device to a personal computer to exchange infor- notebook computer with the mation. Some mobile devices are Internet-enabled, simplicity of pencil and paper. meaning they can connect to the Internet wirelessly. digital pen Because of their reduced size, the screens on handheld computers are small. Introduction to Computers Chapter 1 17 Five popular types of mobile devices are smart phones, PDAs, handheld computers, portable media players, and digital cameras. Smart Phones Offering the convenience of one-handed operation, a smart phone (Figure 1-17) is an Internet- enabled phone that usually also provides personal information management functions such as a calendar, an appointment book, an address book, a calculator, and a notepad. In addition to basic phone capabilities, a smart phone allows you to send and receive e-mail messages and access the Web — usually for an additional fee. Many models also function as a portable media player and include built-in digital cameras so that you can share photos or videos. Many smart phones also offer a variety of application software such as word processing, Figure 1-17 Some spreadsheet, and games. smart phones have touch Many smart phones have keypads that contain both numbers and letters so that you can use the screens; others have mini same keypad to dial phone numbers and enter messages. Others have a built-in mini keyboard. keyboards. Some have touch screens. Instead of calling someone’s smart phone or cell phone, users often send messages to others by pressing buttons on their phone’s keypad, keys on the mini keyboard, or images on an on-screen keyboard. Types of messages users send with smart phones include text messages, instant messages, picture messages, and video messages. A text message is a short note, typically fewer than 300 characters, sent to or from a smart phone or other mobile device. An instant message is a real-time Internet communication, where you exchange messages with other connected users. A picture message is a photo or other image, sometimes along with sound and text, sent to or from a smart phone or other mobile device. A phone that can send picture messages often is called a camera phone. A video message is a short video clip, usually about 30 seconds, sent to or from a smart phone or stylus other mobile device. A phone that can send video messages often is called a video phone. PDAs A PDA (personal digital assistant) provides personal information management functions such as a calendar, an appointment book, an address book, a calculator, and a notepad (Figure 1-18). Most PDAs also offer a variety of other application software such as word processing, spreadsheet, personal finance, and games. A common input device for a PDA is a stylus. Many PDAs are Internet-enabled so that users can check e-mail and access the Web. Some also provide camera and phone capabilities and can function as a portable media player. Figure 1-18 A PDA. Handheld Computers A handheld computer, sometimes referred to as an Ultra-Mobile PC (UMPC), is a computer small enough to fit in one hand. Industry-specific handheld computers serve mobile employees, such as parcel delivery people, whose jobs require them to move from place to place. Portable Media Players A portable media player is a mobile device on which you can store, organize, and play digital media (Figure 1-19). For example, you can listen to music; watch videos, movies, and television shows; and view photos on the device’s screen. With most, you download the digital Figure 1-19 The media from a computer to the portable media player or to media that you iPod, shown here, is a insert in the device. popular portable media player. earbuds 18 Chapter 1 Introduction to Computers Portable media players usually include a set of earbuds, which are small speakers that rest inside each ear canal. Some portable media players have a touch screen; others have a touch-sensitive pad that you operate with a thumb or finger, to navigate through digital media, adjust volume, and customize settings. Digital Cameras A digital camera is a device that allows users to take pictures and store the photographed images digitally, instead of on traditional film (Figure 1-20). Although digital cam- eras usually have some amount of internal storage to hold images, most users store images on small storage media such as memory cards. Digital cameras typically allow users to review, and sometimes modify, images while they are in the camera. Often users prefer to download images from the digital camera to the computer. Digital Cameras Or, you can remove the storage media such For more information, visit Figure 1-20 With a digital camera, users can view scsite.com/dcf2011/ch1/ as a memory card from the digital camera photographed images immediately through a small weblink and then click and insert it in a card reader in or attached screen on the camera to see if the picture is worth Digital Cameras. to the computer. keeping. INNOVATIVE COMPUTING 1-1 Game Consoles Wii a Welcome Medical Skill Builder A game console is a mobile computing device designed for single- A patient awaiting laparoscopic procedures player or multiplayer video games (Figure 1-21). Standard game con- may be less tense knowing that the sur- geons have honed their dexterity and coor- soles use a handheld controller(s) as an input device(s); a television dination using a Nintendo Wii. Preliminary screen as an output device; and hard disks, optical discs, and/or memory studies have found that doctors can improve cards for storage. The compact size and light weight of game consoles their fine motor make them easy to use at home, in the car, in a hotel, or any location control by playing that has an electrical outlet. Three popular models are Microsoft’s Xbox video games that 360, Nintendo’s Wii (pronounced wee), and Sony’s PlayStation 3. Read emphasize subtle Innovative Computing 1-1 for a look at how Nintendo Wii applications hand movements used in minimally are being used in the medical field. invasive surgeries. A handheld game console is small enough to fit in one hand. With Researchers are the handheld game console, the controls, screen, and speakers are built developing Wii into the device. Some models use cartridges to store games; others i l surgery simulators h will that i allow doctors use a memory card or a miniature optical disc. Many handheld game to practice their skills at home or in break consoles can communi- rooms at hospitals. The Wii game system is finding a medical cate wirelessly with other similar consoles for multi- handheld game home in other nontraditional places. Physical console therapists urge arthritic patients to use player gaming. Two popular Wiihabilitation to build endurance and models are Nintendo DS increase their range of motion. Therapeutic Lite and Sony’s PlayStation recreation with the Wii’s sports games may Portable (PSP). help patients recovering from strokes, frac- tures, and combat injuries. In addition to gaming, Researchers in a testing lab in California many game console mod- are experimenting with using the Wii’s els allow users to listen to motion-activated controls in non-gaming music, watch movies, keep applications, such as allowing doctors to fit, and connect to the explain X-ray images to patients. Internet. For more information, visit scsite.com/ dcf2011/ch1/innovative and then click Figure 1-21 Game consoles Medical Wii. game console provide hours of video game entertainment. Introduction to Computers Chapter 1 19 Servers A server controls access to the hardware, software, and other resources on a network and provides a central- ized storage area for programs, data, and information (Figure 1-22). Servers support from two to several thousand connected computers at the same time. People use personal computers or terminals to access Figure 1-22 A server data, information, and programs on a server. A terminal controls access to is a device with a monitor, keyboard, and memory. resources on a network. Mainframes A mainframe is a large, expensive, powerful computer that can handle hundreds or thousands of connected users simultaneously (Figure 1-23). Mainframes store huge amounts of data, instructions, and information. Most major corporations use mainframes for business activities. With mainframes, enterprises are able to bill millions of customers, prepare payroll for thousands of employees, and manage thousands of items in inventory. One study reported that mainframes process more than 83 percent of transactions around the world. Servers and other mainframes can access data and information from a mainframe. People also can access programs on the mainframe using terminals or Figure 1-23 Mainframe computers can personal computers. handle thousands of connected computers and process millions of instructions per second. Supercomputers A supercomputer is the fastest, most powerful computer — and the most expensive (Figure 1-24). The fastest supercomputers are capable of processing more than one quadrillion instructions in a single second. Applications requiring complex, sophisticated mathematical calculations use supercomputers. Large-scale simulations and applications in medicine, aerospace, automotive design, online banking, weather forecasting, nuclear energy research, and petroleum exploration use a supercomputer. Figure 1-24 This supercomputer, IBM's Roadrunner, can process more than one quadrillion instructions in a single second. Embedded Computers An embedded computer is a special-purpose computer that functions as a component in a larger product. A variety of everyday products contain embedded computers: Consumer electronics Home automation devices Automobiles Process controllers and robotics Computer devices and office machines 20 Chapter 1 Introduction to Computers Because embedded computers are components in larger products, they usually are small and have limited hardware. Embedded computers perform various functions, depending on the requirements of the product in which they reside. Embedded computers in printers, for example, monitor the amount of paper in the tray, check the ink or toner level, signal if a paper jam has occurred, and so on. Figure 1-25 shows some of the many embedded computers in cars. Adaptive cruise control systems detect if cars in Advanced airbag systems have front of you are too close crash-severity sensors that determine and, if necessary, adjust the appropriate level to inflate the the vehicle’s throttle, airbag, reducing the chance of airbag may apply brakes, and/or injury in low-speed accidents. sound an alarm. Cars equipped with wireless Tire pressure monitoring communications capabilities, called systems send warning telematics, include such features as signals if tire pressure navigation systems, remote diagnosis is insufficient. and alerts, and Internet access. Drive-by-wire systems sense pressure on the gas pedal and communicate electronically to the engine how much and how fast to accelerate. Figure 1-25 Some of the embedded computers designed to improve your safety, security, and performance in today’s automobiles. Examples of Computer Usage Every day, people around the world rely on different types of computers for a variety of applications. To illustrate the range of uses for computers, this section takes you on a visual and narrative tour of five categories of users: a home user, a small office/home office (SOHO) user, a mobile user, a power user, and an enterprise user. Home User In an increasing number of homes, the computer is a basic necessity. Each family member, or home user, spends time on the computer for different reasons. These include personal financial management, Web access, communications, and entertainment (Figure 1-26). On the Internet, home users access a huge amount of information, conduct research, take college classes, pay bills, manage investments, shop, listen to the radio, watch movies, read books, file taxes, book airline reservations, make telephone calls, and play games. They also communicate with others around the world through e-mail, blogs, instant messages, and chat rooms. Home users share ideas, interests, photos, music, and videos on social networking Web sites. With a digital camera, home users take photos and then send the electronic images to others. Many home users have a portable media player, so that they can listen to downloaded music and/or podcasts at a later time through earbuds attached to the player. They also usually have one or more game consoles to play video games. Today’s homes typically have one or more desktop computers. Some home users network mul- tiple desktop computers throughout the house, often wirelessly. These small networks allow family members to share an Internet connection and a printer. Home users have a variety of software. They type letters, homework assignments, and other docu- ments with word processing software. Personal finance software helps the home user with personal finances, investments, and family budgets. Other software assists with preparing taxes, keeping a Introduction to Computers Chapter 1 21 household inventory, setting up maintenance schedules, and protecting computers against threats and unauthorized intrusions. Reference software, such as encyclopedias, medical dictionaries, or a road atlas, provides valu- able information for everyone in the family. With entertainment software, the home user can play games, compose music, research genealogy, or create greeting cards. Educational software helps adults learn to speak a foreign language and youngsters to read, write, count, and spell. FAQ 1-3 How many households do not use the Internet or Lack of Experience with Technology related technologies? Never searched for information on the Internet A recent survey estimates that 18 percent of U.S. households have Never sent or received no Internet access. Furthermore, about 20 percent of U.S. heads of e-mail messages households have never sent an e-mail message. The chart to the Never looked up a Web site on the Internet right illustrates the lack of experience with computer and Internet Never used a computer technology. to create documents For more information, visit scsite.com/dcf2011/ch1/faq and then 0% 5% 10% 15% 20% 25% 30% click Experience with Technology. Source: Parks Associates personal financial management Web access communications entertainment Figure 1-26 The home user spends time on a computer for a variety of reasons. 22 Chapter 1 Introduction to Computers Small Office/Home Office User Computers assist small business and home office users in managing their resources effectively. A small office/home office (SOHO) includes any company with fewer than 50 employees, as well as the self-employed who work from home. Small offices include local law practices, accounting firms, travel agencies, and florists. SOHO users typically use a desktop computer. Many also use smart phones. SOHO users access the Internet — often wirelessly — to look up information such as addresses, directions, postal codes, flights (Figure 1-27a), and package shipping rates or to send and receive e-mail messages, or make telephone calls. Many have entered the e-commerce arena and conduct business on the Web. Their Web sites adver- tise products and services and may provide a Figure 1-27a (Web access) means for taking orders. To save money on hardware and software, small offices often network their computers. For example, the small office connects one printer to a network for all employees to share. SOHO users often work with basic business software such as word processing and spread- sheet programs that assist with document preparation and finances (Figure 1-27b). They are likely to use other industry-specific types of software. An auto parts store, for example, will have software that allows for looking Figure 1-27b (spreadsheet program) up parts, taking orders and payments, and updating inventory. Mobile User Today, businesses and schools are expanding to serve people across the country and around the world. Thus, increasingly more employees and students are mobile users, who work on a mobile computer or device while away from a main office, home office, or school (Figure 1-28). Some examples of mobile users are sales representatives, real estate agents, insur- Figure 1-27 People with a home office and employees in small offices typically ance agents, meter readers, package delivery use a personal computer for some or all of their duties. people, journalists, and students. handheld notebook computer game console smart phone Tablet PC Figure 1-28 Mobile users have a variety of computers and devices so that they can work, do homework, send messages, connect to the Internet, or play games while away from a wired connection. Introduction to Computers Chapter 1 23 Mobile users often have a mobile computer and/or mobile device. With these computers and devices, the mobile user can connect to other computers on a network or the Internet, often wirelessly accessing services such as e-mail and the Web. Mobile users can transfer information between their mobile devices and another computer. For entertainment, the mobile user plays video games on a handheld game console and listens to music or watches movies on a portable media player. The mobile user works with basic business software such as word processing and spreadsheet software. With presentation software, the mobile user can create and deliver presentations to a large audience by connecting a mobile computer or device to a video projector that displays the presentation on a full screen. Power User Another category of user, called a power user, requires the capabilities of a powerful desktop computer, called a workstation. Examples of power users include engineers, scientists, architects, desktop publishers, and graphic artists (Figure 1-29). Power users typically work with multimedia, combining text, graphics, audio, and video into one application. These users need computers with extremely fast processors because of the nature of their work. The power user’s workstation contains industry-specific software. For example, engineers and architects use software to draft and design floor plans, mechanical assemblies, or vehicles. A desktop publisher uses software to prepare marketing literature. A graphic artist uses software to create sophisticated drawings. This soft- ware usually is expensive because of its specialized design. Power users exist in all types of businesses. Some also work at home. Their computers typically have network connections and Figure 1-29 This graphic artist uses a powerful Internet access. computer to develop computer games. Enterprise User An enterprise has hundreds or thousands of employees or customers that work in or do business with offices across a region, the country, or the world. Each employee or customer who uses a com- puter in the enterprise is an enterprise user (Figure 1-30). Many large companies use the words, enterprise computing, to refer to the huge network of computers that meets their diverse computing needs. The network facilitates communications among employees at all locations. Users access the network through desktop computers, mobile computers, and mobile devices. Enterprises use computers and the computer network to process high volumes of transactions in a single day. Although they may differ in size and in the products or services offered, all generally use computers for basic business activities. For example, they bill millions of customers or prepare payroll for thousands of employees. Some enterprises use blogs to open communications among employees and/or customers. Enterprises typically have e-commerce Web sites, allowing customers and vendors to conduct business online. The Web site showcases products, services, and other company infor- mation. Customers, vendors, and other interested parties can access this information on the Web. The marketing department in an enterprise uses desktop publishing software to prepare marketing literature. The accounting department uses software for accounts receivable, Figure 1-30 An enterprise can have hundreds or thousands accounts payable, billing, general ledger, and payroll activities. of users in offices across a region, the country, or the world. 24 Chapter 1 Introduction to Computers Enterprise users work with word processing, spreadsheet, database, and presentation software. They also may use calendar programs to post their schedules on the network. And, they might use smart phones or other mobile devices to maintain contact information. E-mail programs and Web Enterprise browsers enable communications among employees, vendors, and customers. Computing Many employees of enterprises today telecommute. Telecommuting is a work arrangement in For more information, visit scsite.com/dcf2011/ch1/ which employees work away from a company’s standard workplace and often communicate with weblink and then click the office through the computer. Employees who telecommute have flexible work schedules so that Enterprise Computing. they can combine work and personal responsibilities, such as child care. Computer Applications in Society The computer has changed society today as much as the industrial revolution changed society in the eighteenth and nineteenth centuries. People interact directly with computers in fields such as education, finance, government, health care, science, publishing, travel, and manufacturing. In addition, they can reap the benefits from breakthroughs and advances in these fields. The following pages describe how computers have made a difference in people’s interactions with these disciplines. Read Looking Ahead 1-1 for a look at how embedded computers may improve the quality of life. LOOKING AHEAD 1-1 Embedded Computers May Improve Quality of Life The weather forecast may be as close as your fingertips if plans to integrate embedded computers in y y objects everyday j become a reality. Researchers are envisioning an umbrella with an embedded cell phone in the handle that will dial and then download the local forecast. The handle will glow g green for good weather and flash red for imminent storms. Dancers can pin a small flower with an embedded motion-detecting computer to their c clothes. When they move, the embedded computer senses action and then synchronizes th tempo of music to this movement. Other embedded computers woven into clothing the c monitor heart and breathing rates. can Wearing hidden embedded computers can help the elderly and people recovering fr accidents and surgeries monitor their walking stride and pace. When their steps from are uneven uneven, the eembedded computer can sound a warning and perhaps prevent a fall. Other embedded computers can give subtle feedback on the quality of physical activity. For more information, visit scsite.com/dcf2011/ch1/looking and then click Embedded Computers. Education Education is the process of acquiring knowledge. In the traditional model, people learn from other people such as parents, teachers, and employers. Many forms of printed material such as books and manuals are used as learning tools. Today, educators also are turning to computers to assist with education (Figure 1-31). Many schools and companies equip labs and class- rooms with computers. Some schools require students to have a mobile computer or mobile device to access the school’s network or Internet wirelessly. Students use software to assist with learning or to complete assignments. To promote education by Figure 1-31 In some schools, students computer, many vendors offer substantial student have mobile computers on their desks discounts on software. during classroom lectures. Introduction to Computers Chapter 1 25 Sometimes, the delivery of education occurs at one place while the learning occurs at other locations. For example, students can take a class on the Web. More than 70 percent of colleges offer distance learning classes. A few even offer entire degrees online. Finance Many people and companies use computers to help manage their finances. Some use finance software to balance checkbooks, pay bills, track personal income and expenses, manage investments, and evaluate finan- cial plans. This software usually includes a variety of online services. For example, computer users can track investments and do online banking. With online banking, users access account balances, pay bills, and copy monthly transactions from the bank’s computer right into their computers (Figure 1-32). Investors often use online investing to buy and sell stocks and bonds — without using a broker. Figure 1-32 An online banking Web site. With online investing, the transaction fee for each trade usually is much less than when trading through a broker. Government A government provides society with direction by making and administering policies. To provide citizens with up-to-date informa- tion, most government offices have Web sites. People access gov- ernment Web sites to file taxes, apply for permits and licenses, pay parking tickets, buy stamps, report crimes, apply for financial aid, and renew vehicle registrations and driver’s licenses. Employees of government agencies use computers as part of their daily routine. Military and other agency officials use the U.S. Department of Homeland Security’s network of information about domestic security threats to help protect our nation. Law enforce- ment officers have online access to the FBI’s National Crime Information Center (NCIC) through in-vehicle computers, finger- print readers, and mobile devices (Figure 1-33). The NCIC contains Figure 1-33 Law enforcement officials have more than 52 million missing persons and criminal records, includ- in-vehicle computers and mobile devices to access ing names, fingerprints, parole/probation records, mug shots, and emergency, missing person, and criminal records in other information. computer networks in local, state, and federal agencies. Health Care Nearly every area of health care uses computers. Whether you are visiting a family doctor for a regular checkup, having lab work or an outpatient test, or being rushed in for emergency surgery, the medical staff around you will be using computers for various purposes: Doctors use the Web and medical software to assist with researching and diagnosing health conditions. Doctors use e-mail to correspond with patients. Pharmacists use computers to file insurance claims. Robots deliver medication to nurse stations in hospitals. Hospitals and doctors use computers and mobile devices to maintain and access patient records. 26 Chapter 1 Introduction to Computers Computers and computerized devices assist doctors, nurses, and technicians with medical tests (Figure 1-34). Computers monitor patients’ vital signs in hospital rooms and at home. Surgeons implant computerized devices, such as pacemakers, that allow patients to live longer. Surgeons use computer-controlled devices to provide them with greater precision during operations, such as for laser eye surgery and robot-assisted heart surgery. Figure 1-34 Doctors, nurses, technicians, and other Two forms of long-distance health care

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