Understanding Computers: Today and Tomorrow 15th Edition PDF

# Understanding Computers: Today and Tomorrow - 15th Edition ## Chapter 1: Introduction to the World of Computers ### Learning Objectives 1. Explain why it is essential to learn about computers today and discuss several ways computers are integrated into our business and personal lives. 2. Define...

# Understanding Computers: Today and Tomorrow - 15th Edition ## Chapter 1: Introduction to the World of Computers ### Learning Objectives 1. Explain why it is essential to learn about computers today and discuss several ways computers are integrated into our business and personal lives. 2. Define a computer and describe its primary operations. 3. List some important milestones in computer evolution. 4. Identify the major parts of a personal computer, including input, processing, output, storage, and communications hardware. 5. Define software and understand how it is used to instruct the computer what to do. 6. List the six basic types of computers, giving at least one example of each type of computer and stating what that computer might be used for. 7. Explain what a network, the Internet, and the World Wide Web are, as well as how computers, people, and Web pages are identified on the Internet. 8. Describe how to access a Web page and navigate through a Web site. 9. Discuss the societal impact of computers, including some benefits and risks related to their prominence in our society. ### Overview This chapter covers: - What computers are, how they work, and how they are used - Computer terminology - An overview of the history of computers - The basic types of computers in use today - How to access resources on the Internet - Societal impacts of computers ### Computers in Your Life - **Why learn about computers?** - **Pervasive computing**, also known as ubiquitous computing. Computers have become an integral part of our lives. - **Basic computer literacy:** Understanding what a computer is and how it works. - **Before 1980:** Computers were large and expensive, very few people had access to them. Computers were mostly used for high-volume processing tasks. - **Microcomputers in the early 1980s:** Inexpensive personal computers emerged. Computer use increased dramatically. - **Today:** Nearly 90% of US households include a computer, and most use computers at work. Electronic devices are converging into single units with multiple capabilities. Computer literacy is an essential skill for everyone. #### Figure 1-1: Convergence: Many devices today include computing or Internet capabilities. * **Televisions:** Can be used to access Web pages, e-mail, streaming movies, and other Internet content, in addition to viewing TV content. * **Smartphones:** Can be used to access Internet content, play music and games, take photos, watch TV shows, and more, in addition to making phone calls. ### Computers in the Home - Computers used for a variety of tasks: looking up information and news, exchanging e-mail, shopping and paying bills, watching TV and videos, downloading music and movies, organizing digital photographs, playing games, making vacation plans. - Used for reference, productivity, and entertainment. - **Wireless networking:** Computers can be used in nearly any location. - **Smart appliances:** Traditional appliances with built-in computer or communication technology. - **Smart homes:** Household tasks are monitored and controlled by a main computer in the house. ### Computers in Education - Youth today: the computing generation. - **Computer labs and classrooms:** Most students today have access to computers at school. Some schools integrate e-books into the curriculum. - **Wireless hotspots:** Colleges and universities are even more integrated. Some have computer requirements for enrollment (supplied or BYOD) - **Distance learning:** Students participate from locations other than the traditional classroom setting using computers and Internet access. #### Figure 1-3: Computer use in education. * **Computer labs and classrooms:** Many schools today have computers and Internet access available in the classroom and/or a computer lab for student use. * **Campus wireless hotspots:** Many students can access the Internet from anywhere on campus to do research, check e-mail, and more, via a campus hotspot. * **Distance learning:** With distance learning, students (such as U.S. Army soldiers) can take classes from home or wherever they happen to be at the moment. ### Computers on the Job - Computers have become a universal on-the-job tool for decision-making, productivity, and communication. - By all types of employees. - For access control and other security measures. - For service professional use. - Extensively by the military. - Requires continually refreshing computer skills. - **Common uses:** decision making, productivity, off-site communications, and authentication. #### Figure 1-4: Computer use on the job. * **Decision making:** Many individuals today use a computer to help them make on-the-job decisions. * **Productivity:** Many individuals today use a computer to perform on-the-job tasks efficiently and accurately. * **Off-site communications:** Many individuals use portable computers or mobile devices to record data, access data, or communicate with others when they are out of the office. * **Authentication:** Many individuals are required to use authentication systems to punch in and out of work, access facilities, or log on to company computers. ### Computers on the Go - Computers are encountered in nearly every aspect of daily life. - Consumer kiosks. - ATM transactions. - POS systems at retail stores. - Self-checkout systems. - Consumer authentication systems. - Portable computers or mobile devices. - GPS systems. ### Technology and You Box: Restaurant iPad Ordering Systems - Used in conjunction with e-menus. - Customers can place and pay for orders. - Can provide more resources to customers. ### What Is a Computer and What Does It Do? - **Computer:** A programmable, electronic device that accepts data, performs operations on that data, and stores the data. It follows instructions, called programs, which determine the tasks the computer will perform. - **Basic Operations:** - **Input:** Entering data into the computer. - **Processing:** Performing operations on the data. - **Output:** Presenting the results. - **Storage:** Saving data, programs, or output for future use. - **Communications:** Sending or receiving data. #### Figure 1-6: The information processing cycle. * **Input:** The user types in the numbers 2 and 5. * **Processing:** The computer adds 2 and 5. * **Output:** The computer displays the results. * **Storage:** The computer saves the output for future use. ### Data vs. Information - **Data:** Raw, unorganized facts. Can be in the form of text, graphics, audio, or video. - **Information:** Data that has been processed into a meaningful form. - **Information Processing:** Converting data into information. ### Computers Then and Now - The computer as we know it is a fairly recent invention. - The history of computers is often referred to in terms of generations. - Each new generation is characterized by a major technological development. - **Precomputers and early computers (before approx. 1946):** Abacus, slide rule, mechanical calculator, Punch Card Tabulating Machine and Sorter. - **First-generation computers (1946-1957):** Enormous and powered by vacuum tubes. Used a great deal of electricity and generated a lot of heat. Examples: ENIAC and UNIVAC. - **Second-generation computers (1958-1963):** Used transistors. Computers were smaller, more powerful, cheaper, more energy-efficient, and more reliable. Punch cards and magnetic tape were used to input and store data. - **Third-generation computers (1964-1971):** Used integrated circuits (ICs), also known as microchips. Computers were even smaller, more powerful, and more reliable than previous generations. - **Fourth-generation computers (1971-present):** Microprocessors were introduced, a single chip containing the CPU with much of the computer’s memory, input, and output controls. Computers became smaller, more affordable, and more powerful. - **Fifth-generation (now and the future):** In infancy stage. May be based on artificial intelligence (AI). Will likely use voice and touch input. May be based on optical computers and utilize nanotechnology. #### Figure 1-7: A brief look at computer generations. * **Fifth-generation computers:** Some aspects of fifth-generation computers, such as the natural language input and artificial intelligence used by the IBM Watson computer shown competing on *Jeopardy!* here, already exist. ### Hardware - **Hardware:** The physical parts of a computer. - **Internal hardware:** Located inside the main box (system unit) of the computer. - **External hardware:** Located outside the system unit. Connect to the computer via a wired or wireless connection. - Hardware devices are associated with all five computer operations. - **Input Devices:** Used to input data into the computer. Examples: keyboards, mice, scanners, cameras, microphones, touch pads, touch screens, fingerprint readers, etc. - **Processing Devices:** Perform calculations and control computer’s operation. Examples: Central processing unit (CPU) and memory. - **Output Devices:** Present results to the user. Examples: monitors, printers, speakers, projectors, etc. - **Storage Devices:** Used to store data on or access data from storage media. Examples: hard drives, CD/DVD discs and drives, USB flash drives, etc. - **Communications Devices:** Allow users to communicate with others and to electronically access remote information. Examples: modems, network adapters, routers, etc. #### Figure 1-9: Typical computer hardware * **Flash memory card reader** * **DVD drive** * **Hard drive** * **System unit** * **Monitor** * **Printer** * **Microphone** * **Speakers** * **USB ports that connects external devices** * **Keyboard** * **CD and DVD discs** * **Mouse** * **Flash memory cards** * **USB flash drive** * **Router** * **Modem** ### Software - **Software:** The programs or instructions used to tell the computer hardware what to do. - **System Software:** Operating system starts up the computer and controls its operation. Without an operating system, the computer cannot function. Booting the computer and launches programs at the user’s direction. Most use a GUI to interact with the user via icons, buttons, tiles, etc. Examples: Windows, Mac OS, Linux, Android, etc. - **Windows 8 interface:** Start button, Start screen, tiles, charms, etc. #### Figure 1-10: The Windows desktop. ### Application Software - **Application Software:** Performs specific tasks or applications. Examples: creating letters, budgets, etc., managing inventory and customer databases, editing photographs, scheduling appointments, viewing Web pages, exchanging e-mail, burning DVDs, designing homes, playing games. - **Examples of application software:** Word processing programs, Multimedia programs, Web browsers, E-mail programs. #### Figure 1-11: Examples of application software * **Word processing Programs:** Allow users to create written documents, such as reports, letters, and memos. ### Computer Users and Professionals - **Computer Users (end users):** People who use a computer to obtain information. - **Computer professionals:** - **Programmers:** Write programs computers use. - **Systems analysts:** Design computer systems. - **Computer operations personnel:** Manage day-to-day computer operations. - **Security specialists:** Secure computers and networks against hackers. ### Quick Quiz 1. Which of the following was not a first generation computer? a. IBM PC b. UNIVAC c. ENIAC 2. True or False: A window displayed when the computer needs more information from the user is called a dialog box. 3. Speakers are an example of a(n) _____ device. **Answers:** 1) a; 2) True; 3) output ### Computers To Fit Every Need - **Six basic categories of computers:** - **Embedded computers:** Embedded into a product and designed to perform specific tasks or functions for that product. Cannot be used as general-purpose computers. Often embedded into: household appliances, thermostats, sewing machines, treadmills, answering machines, cars. - **Mobile devices:** A very small device with some type of built-in computing or Internet capability. Typically has a small screen and keyboard. Examples: smartphones, handheld gaming devices, portable digital media players, media tablets. - **Personal computers:** Small computer designed to be used by one person at a time. Also called a microcomputer. Available in different sizes and shapes. - **Desktop Computers:** On or next to a desk. Tower case, desktop case, or all-in-one. PC or Macintosh. Not portable. - **Portable Computers:** Designed to be carried around easily. Fully functional computers. - **Notebook (laptop) computers:** Typically use a clamshell design. - **Tablet computers:** Usually use a digital pen/stylus or touch screen. No physical keyboard; can use on-screen or attached keyboard. - **Hybrid notebook-tablet computers** - **Netbooks:** Smaller and have more limited features than conventional notebooks - **Servers:** A medium-sized computer used to host programs and data for a small network. Sometimes referred to as a minicomputer. Users connect via a network with a computer, thin client, or dumb terminal. **Virtualization:** Creating virtual rather than actual environments (often used to share a server for increased efficiency). - **Mainframe computers:** Powerful computer used by many large organizations to manage large amounts of centralized data. Standard choice for hospitals, universities, large businesses, banks, government offices. Located in climate-controlled data centers and connected to the rest of the company computers via a network. Larger, more expensive, and more powerful than servers. Usually operate 24 hours a day. Also called high-end servers or enterprise-class servers. - **Supercomputers:** Fastest, most expensive, most powerful type of computer. Generally run one program at a time, as fast as possible. Can cost several million dollars each. Tend to be very large and contain a large number of CPUs. Titan is one of the fastest computers in the world. #### Figure 1-12: Embedded computers * **A camera located under the mirror detects moving vehicles in the driver’s blind spot.** * **A light indicates that a moving vehicle is in the driver’s blind spot.** #### Trend Box: Tiny PCs - **Tiny PCs:** Can look like a USB flash drive or small circuit board. Typically connect your TV to the Internet to display Web content. Some are full computers. #### Figure 1-13: Mobile devices * **Smartphones** * **Media tablets** #### Figure 1-14: Desktop Computers * **Tower Computers** * **All-in-one Computers** #### Figure 1-15: Portable Computers * **Notebooks:** * **Tablets:** * **Hybrid Notebook-Tablets:** #### Figure 1-17: Servers * **Servers:** Servers are used to host data and programs on a small network, such as a school computer lab or medical office network. #### Figure 1-18: Mainframe computers. * **Mainframe computers:** Mainframes are used to perform large processing tasks for businesses. #### Figure 1-19: The Titan supercomputer. * **Supercomputers:** Supercomputers are used for specialized situations in which immense processing speed is required. ### Quick Quiz 1. A tablet PC is an example of a(n) ______. a. Desktop Computer b. Portable PC c. Internet appliance 2. True or False: The terms mainframe computer and supercomputer are interchangeable; both refer to the largest, most powerful computers. 3. A smartphone is an example of a(n) ______. **Answers:** 1) b; 2) False; 3) mobile device ### Computer Networks and the Internet - **Computer Network:** A collection of hardware and other devices that are connected together. Users can share hardware, software, and data. Users can communicate with each other. - **Network Servers:** Manage resources on a network. - Computer networks exist in many sizes and types: Home networks, School and small office networks, Large corporate, Public wireless networks, Mobile telephone networks. #### Figure 1-20: Example of a computer network. - **The Internet:** The largest/most well-known computer network in the world. Individuals connect using an Internet service provider (ISP) - **World Wide Web:** One resource (a vast collection of Web pages) available through the Internet. Web sites contain Web pages stored on Web servers. Viewed using a Web browser (Internet Explorer, Chrome, Safari, Firefox, Opera, etc.). Offers a wide variety of information. #### Figure 1-21: Some common Web activities * **Looking up information** * **Accessing social networks** * **Watching videos, TV shows, and movies** ### Accessing a Network or the Internet - Need a modem or network adapter to connect. - Some networks require a username and password. - Internet connections can be: - Direct (always-on) connections. - Dial-up connections. - Internet addresses are used to access resources on the Internet. - **IP (Internet Protocol) address:** Numeric address that identifies computers (207.46.197.32). - **Domain Names:** Correspond to IP addresses. **Top-level domains (TLDs)** identify type of organization or its location. #### Figure 1-22: Sample top-level domains (TLDs). - **Uniform Resource Locators (URLs):** Uniquely identify a Web page, including: protocol or standard being used, Web server hosting the page, names of folders in which the Web page file is stored, Web page's filename. - **Protocols:** Hypertext Transfer Protocol (http://) is typically used to display Web pages. (https:// is used for secure Web pages). File Transfer Protocol (ftp://) is often used for file exchange. #### Figure 1-23: A Web page URL. - **E-mail addresses:** Consists of: username (an identifying name), the @ symbol, and domain name for the computer that will be handling the person's e-mail (mail server). - **Pronouncing Internet addresses:** - **Domain name:** berkeley dot e du - **URL:** microsoft dot com slash windows slashi e slash default dot as p - **E-mail address:** president at white house dot gov #### Figure 1-24: Pronouncing Internet addresses. ### How It Works Box: Campus Emergency Notification Systems - Enable students and teachers to be notified of dangerous activity, weather, etc., in a timely manner. - Can be sent via text messages, e-mail messages, Facebook pages, Twitter feeds, digital signage systems, etc. ### Surfing the Web - **Web browser:** Used to display Web pages. - **Browser starting page or home page:** The first page displayed when the browser is opened. - To navigate to a Web page, you can: - Type a URL in the Address bar. - Click a hyperlink: graphics or text linked to other Web pages. - Select a Favorite/Bookmark or page from the History list. ### Searching the Web - **Search site:** Helps you locate what you are looking for. Typically search using keywords. - **Reference sites:** Look up addresses, telephone numbers, ZIP codes, maps, etc. #### Figure 1-26: The Google search site displayed in the Chrome browser. ### E-Mail - **Electronic mail (e-mail):** Electronic messages exchanged between computers on a network. - One of the most widely used Internet applications. - Can be conventional e-mail program, Web-based, or mobile-based. - **Conventional:** Microsoft Outlook, Mac OS X Mail - **Web-based:** Gmail, Outlook.com - Can contain photos, attached files, etc. - Mobile e-mail may require a fee. - Other types of mobile communications: - Short Message Service (SMS) - Multimedia Message Service (MMS) #### Figure 1-27: How e-mail works * **Sender's computer:** The sender composes a message and sends it to the recipient via his or her e-mail address. * **Sender's mail server:** The e-mail message is sent over the Internet through the sender’s mail server to the recipient's mail server. * **Recipient's mail server:** The recipient requests his or her messages from the mail server and the message is displayed. * **Recipient's computer:** ### Computers and Society - The vast improvements in technology over the past decade have had a distinct impact on daily life, at home and at work. - Many benefits of a computer-oriented society: - Ability to design products before construction leads to safer products. - Earlier medical diagnoses and more effective treatment. - Devices that allow physically and/or visually challenged individuals to perform job tasks. - Documents e-mailed or faxed in moments. - Download information, music, programs, movies, and more on demand. - Computer-oriented society also has risks: - Stress and health concerns. - Spam. - Computer viruses and malware. - Identity theft and phishing. - Privacy issues: How data is collected. How secure is the collected data. - Differences in online communications are less formal than traditional. - **Netiquette:** Be polite and considerate of others. Refrain from offensive remarks. - **Abbreviations (acronyms) and emoticons:** Acronyms, such as BTW (by the way). Illustrations of faces, such as #### Figure 1-30: Netiquette - Use short, descriptive subject lines for e-mail messages and online posts. - Don't shout in all capital letters. - Watch what you say or write online. - Don’t spam your contacts. - Be cautious when meeting people online. - Think before you send or post. ### The Anonymity Factor - Gives many individuals a sense of freedom. - Can also be abused. ### Information Integrity - Use common sense when evaluating online content. - Check your source—not all information on the Internet is accurate. ### Quick Quiz 1. Index.html is an example of a(n) ______. a. URL b. IP address c. Web page filename 2. True or False: All information published to Web pages is accurate. 3. In the e-mail address [email protected], abc.com is the ______. **Answers:** 1) c; 2) False; 3) domain name ### Summary - Computers in Your Life - What is a Computer and What Does It Do? - Computers to Fit Every Need - Computer Networks and the Internet. - Computers and Society