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1、1. INFORMATION TECHNOLOGY, THE INTERNET, AND YOUL The purpose of this book is to help the student become computer literate Competent in computer-related skills The goal is to be valuable immediately to a potential employer Chapter one gives an overview of an information system This system consists o
2、f the following: People Procedures Software Hardware Data4. Define an information system Some students may think of a system as pertaining to just the hardware Remind them that a microcomputer is part of an information system To be competent end user, one must understand the essentials of IT Note th
3、at IT stands for information technology5. People are the most important part of an information system Our lives are touched everyday by computers Have students give examples of how they use computer applications throughout the day Some examples are: instant messaging Web-based applications personal
4、website virus protection TV tuners and video clips digital photography music home networking spyware job opportunities6. Emphasize differences between application and systems software System software operating system utilities device drivers Application software general purpose special purpose7.Soft
5、ware is another name for programs Programs are instructions that tell the computer how to process data into the form you want Two major kinds of software System Not a single program a collection of programs Operating systems Windows XP Mac OS X Utilities Service programs Performs tasks related to ma
6、naging computer resources Device drivers Application8. “End-user“ software - people who use microcomputer or have access to larger computers Nearly everyone in todays workforce and general public have access, These people enter commands and typically interact with application programs. Two major cat
7、egories General - purpose or basic programs; off-the-shelf Specialized - written for an organizations or business types specific purpose; specially written9. Examples of hardware: Disk drive, keyboard, printer and modem are different types of computer hardware 10. There are four types of computers,
8、Supercomputers Mainframe computers Minicomputers Microcomputers desktop laptop or notebook tablet PC, Handheld computers Palm computers Persona digital assistants 11. Above is an example of a Cray supercomputer, which, unlike the illustration, is always in an air conditioned box This is required bec
9、ause of the heat generated during processing A major reason for its processing speed is shorted connection wires throughout the interior Of course, shorter wires means faster byte transfer times Supercomputers are the most powerful type of computer NASA uses supercomputers to track and control space
10、 exploration 12. Mainframes occupy specially wired, air-conditioned rooms Not as powerful as supercomputers Insurance, financial and equity industries, as well as governments all process large amounts of information on mainframes13. These are refrigerator sized machines Production departments use mi
11、nicomputers to monitor certain manufacturing processes and assembly line operation s Problem is most current desktops have capacity of many minicomputers.14. Lease powerful computers, but most widely used Fastest growing computer Have students begin discussing the microcomputer and wireless connecti
12、vity 15. System Unit Memory CPU I/O Devices Monitors Printers Secondary Storage Floppy Hard drive Optical disks Monitors include LCD panels and traditional CRTs. Current trends regarding monitors; sizes depending upon use of system Communications Modems - equipment that translates data from the CPU
13、to a form humans can understand16. Used to describe facts about something Contained in files for documents, worksheets and databases Document files - usually created by word processors Worksheet files - electronic spreadsheets Database files - electronic database management programs Presentation Fil
14、es - electronic slides shows 17. Connectivity is the capability of your microcomputer to share information with other computers Wireless /mobile communication devices are more popular than ever A network is central to the concept of connectivity Ask students questions about the Internet. Here are so
15、me facts: No one owns the Internet There is no Internet, Inc. The Internet is a network of networks The WWW provides multimedia interface to resources on the Internet 18. Using information technology means being computer competent The Internet and the Web are the two most important technologies of t
16、he 21st century Software can now do extraordinary tasks Microcomputers are more powerful Society must be careful about protecting their privacy Almost all organizations rely on information systems2. THE INTERNET, THE WEB, AND ELECTRONIC COMMERCE 1. Ask the students why the Internet is often referred
17、 to as the Information Superhighway Competent end users need to be aware of the resources available on the Internet and the Web Ask students to list the resources they use on the Web 3. Most developed network system currently in use; connects people all over the world Originally started in 1969 when
18、 US funded a research project (ARPANET). CERN - Center for European Nuclear Research World Wide Web (Web) is a part of the Internet - not the Internet; introduced in 1992 by consortium in Switzerland. Originally started as research and text-based network to exchange research ideas from university to
19、 university Developed into a network of networks One of the most powerful tools of the 21st century 4. Most common Internet applications Communicating - sending e-mail and discussion group participation You can chat live with others Ask students what chat software they use Shopping - fastest growing
20、 applications Searching - using virtual libraries, Entertainment - increased use of DVD; integration of TV and PC Education ore-learning You can take classes on almost any subject 5., The common way to access the Internet is through a provider or host computer Providers - already connected to the In
21、ternet - furnish a pathway for other users Typical providers include: Colleges and universities - usually free” Internet service providers (ISP) can be local (regional) or national Ask students to identify various ISPs used in their environment Types of providers National - like AOL Regional - small
22、er service area Wireless no telephone lines used provide connection through wireless modems6. Browsers allow you to search or surf the Web Navigate search for information and communicate using the Web Use URL (uniform resource locator) to connect to other resources Two parts to URL: protocol (usuall
23、y http:/); second is domain name or server where resource located ()7. Browser is software that allows users to navigate the Web and read the multimedia formatted pages Connect to Web sites using URL addresses (uniform resource locator) Document is sent to computer usually coded in HTML (hypertext m
24、arkuplanguage) or some variation Interprets the HTML codes displaying page May contain Hyperlinks allow users to quickly connect to other pages or Web sites Graphics Text8. Web pages contain links to programs called applets These are special programs written in a programming language called Java The
25、se programs can be quickly downloaded and run by most browsers9. Communications is the most popular Internet activity Types of communications: E-mail or electronic mail, Transmission of electronic messages over the Internet, Has three basic parts: header, message, and signature Header Address Subjec
26、t very important to include this in a message Attachments Spam - unsolicited e-mail Distraction, Nuisance, Discussion groups Participate in forums and debates Includes mailing lists, newsgroups, chat groups, and instant messaging Mailing lists - message is sent to a list of addresses Newsgroups - us
27、es a special network called UseNet Chat - allows direct, live communications IRC - Internet Relay Chat is a very popular chat service IM - instant messaging can send messages back and forth in real time Lurking - this is a technique you can use before you participate in a discussion group You observ
28、e and dont respond until you feel more comfortable with the group Discussion groups10. The most common Internet activity With Internet access and an e-mail program, one can reach anybody in the world similarly equipped An e-mail message has three basic elements Header - subject, address and attachme
29、nts Message Signature Internet addresses use the domain name system. Personal Information Managers - helps in organization and communication with others Electronic Daytimers plus ability to communicate through Internet11. Internet uses the domain name system (DNS), which gives names and numbers to p
30、eople and computers Address has three parts User name - identifies unique user or computer in the domain Domain name - references a specific organization Domain code - geographical location or organizational identification, Domain identification =.com = commercial =.edu = education and research =,or
31、g = organizations (usually non-profit) =.net = major network centers (usually easier to access than commercial) =.gov = government12. Mailing lists send e-mail to all members. Sign up, Messages sentUnsubscribe Newsgroups use the Usenet. Most popular discussion group Located on a special network call
32、ed UseNet Chat groups support live conversations. IRC favorite of many users Allow live communication in real time Communication by typed messages Lurking is good - Reading communications before contributing Helps potential participants understand the culture of the group Uses lists (instant messagi
33、ng) to activate notification when live Must join, then sign on to participate Individual communication Group communication Use lists are more private than Chat groups 13.Ask students to give examples of the each of the above discussion group terms 14. Specialized programs that assist you in locating
34、 information on the Web and the Internet Search services ( providers) help you locate information; they maintain the database that helps you get where you want Special programs called agents, spiders, or bots, continually look for infb and updated services Search engines - assist you to locate infor
35、mation Examples AltaVista Excite Google Northern Light Teoma Yahoo! use keyword search; know “rules i.e. use + or quotes to look for phrases rather than individual words use directory search - list of categories or topics; also known as index search Metasearch engines - programs that automatically s
36、ubmit your search request to several search engines simultaneously.15. Keyword search - enter a keyword or a phrase Returns a number of hits, Each hit includes a hyperlink Directory search Known as an index search Select a category or topic that fits the information you want Note: a recent study by
37、the NEC Research Institute found that any one search engine includes only a fraction of the informational sources on the Web16. Programs that automatically submit your search request to several engines simultaneously The engine receives the results, eliminates duplicates, orders hits, and then provi
38、des the edited list to you17. Electronic commerce is buying and selling over the Internet Three basic types of electronic commerce: business to consumer; consumer to consumer; and business to business Web storefronts are virtual stores for B2C commerce; just like being in the store except you do it
39、from home Web auctions growing in popularity; similar to traditional auctions no one sees each other Auction house sites - merchandise presented for auction, Person-person auction sites - more like flea markets; forum for buyers and sellers to gather Electronic payment - easy, secure payment method
40、Checks - slowest and least convenient Credit cards - Easier to work with, Somewhat vulnerable to theft Electronic cash or e-cash - also known as cybercash and digital cash, Purchased from third party (usually a special bank); More secure than credit cards18. Virtual stores for B2C electronic commerc
41、e Shoppers visit stores on the Web to inspect merchandise and make purchases 19. Similar to Web traditional auctions Buyers and sellers seldom meet face-to-face Ask the students if they have ever used E-bay 20. A challenge is the payment for goods Should be reliable, secure, and fast21. Telnet runs
42、programs on remote computers; connect to another computer and run programs on it FTP transfers files; file transfer protocol; Internet service for file transfer Downloading - transmitting files from the host to client Uploading - transmitting files from the client to host Plug-ins - automatically lo
43、aded by and work with your browser; Acrobat Reader; Cosmos from Silicon Graphics (3-d displays); Media Player; Quicktime from Apple; RealPlayer; and Shock wave from Macromedia Helper applications are independent programs executed from your browser designed tomaximize your efficiency Off-line browser
44、s - Off-line search utilities auto submit your search info to variety of engines and create an index for your review; auto save HTML docs to your hard drive Information pushers - User selects topic areas or channels of interest Program retrieves relevant information from the Web and stores it for vi
45、ewing at the convenience of the user Filters - block access to specified sites; set time limits 22. Internet2 is a collaborative project between an assembly of universities, the government, and private resource groups Faster downloads and less waiting time are some of the advantages3. BASIC APPLICAT
46、ION SOFTWARE1. The microcomputer can help you do many things - think of it as an electronic tool The right kind of software is needed 4. Use the application for which it was designed: if you want to process text, use word If need to sort information, use database rather than spreadsheet Can create publications with Word; but presentation software and desktop publishing software are designed to do this type of task easier Specialized Applications Called special purpose applications Common types Graphics Audio/video editors Multimedia creation Web authoring