1. Computer Fundamentals Lecture 12 MSCH 233

2. Electronic Communications How can a PC be connected to another computer? How can a PC be connected to another computer? What data communication systems can you think of? What data communication systems can you think of?

3. Data Communications Services Data Communications Service Service provided Fax To send a copy of a paper document from one place to another via phone line Electronic e-mail To send a personal message to another person on a different workstation Teletext To find out weather forecasts and sports information on the television Local Bulletin board systems To receive shareware and public domain programs from a user group Commercial online services To access massive databases containing all kinds of information

4. Transferring information from one PC to another via modem and phone lines (or fiber-optic cables). Telecommunications Translates signals from digital to analog and vise versa

5. What do we need to telecommunicate? PC PC Modem Modem Phone line Phone line Communications software Communications software Online service provider Online service provider

6. Internet Issues Is it technically possible for computer criminals to infiltrate into the Internet and steal sensitive information? Is it technically possible for computer criminals to infiltrate into the Internet and steal sensitive information? What is a hacker? What is a hacker? Can viruses enter your PC from the internet? Can viruses enter your PC from the internet?

7. Important Terms Hacker: a person who obtains unauthorized access to computer data. Hacker: a person who obtains unauthorized access to computer data. Cookies: small files on the web server to know if you have visited the site before. Cookies: small files on the web server to know if you have visited the site before. Certificates: files that identify users on the net, like digital identification card. Certificates: files that identify users on the net, like digital identification card. Encryption: the process on encoding data so that unauthorized users can not read it. Encryption: the process on encoding data so that unauthorized users can not read it. Decryption: the process of decoding encrypted data transmitted to you. Decryption: the process of decoding encrypted data transmitted to you.

8. Security on the Web Data can technically be copied by hackers if you are not alert. Data can technically be copied by hackers if you are not alert. Set all our security alerts to high on your web browser. Set all our security alerts to high on your web browser. If you use online banking, make sure your bank uses digital certificates. If you use online banking, make sure your bank uses digital certificates.

9. E-mail Privacy E-mail messages can be read by hackers. E-mail messages can be read by hackers. to protect your self, encrypt your message with proper software. to protect your self, encrypt your message with proper software.

10. Network Security Networks can be attacked by intruders. Networks can be attacked by intruders. companies need to build a high security system to protect it self. companies need to build a high security system to protect it self. Using access passwords, encryption and firewalls will help a lot. Using access passwords, encryption and firewalls will help a lot.

11. Virus Protection Viruses can enter a PC through floppy disks, the Internet or Bulletin board systems. Viruses can enter a PC through floppy disks, the Internet or Bulletin board systems. Do not open any e-mail message you get. Do not open any e-mail message you get. be alert when downloading files from the web. be alert when downloading files from the web. Install n up-to-date anti-virus software. Install n up-to-date anti-virus software.

12. Computer Fundamentals Lecture 13 MSCH 233

13. LANs and WANs What is a computer network? What is a computer network? What are the benefits of connecting computers and peripherals? What are the benefits of connecting computers and peripherals?

14. What is a computer network? A network is a group of devices connected by communications circuits so that users can share data, programs and hardware resources. A network is a group of devices connected by communications circuits so that users can share data, programs and hardware resources.

15. Main elements of a network 1. Physical structure; which links the equipment. 2. Software; which allows communications.

16. What is a LAN? A network contained in a relatively small area.

17. What is a WAN? A network for long distance or world wide communications.

18. How can we link Networks? Telephone lines Telephone lines Fiber-optic cables Fiber-optic cables Satellite Satellite

19. New Technologies 1. Mobile phones displaying internet information  Third generation mobiles ( transmit picture and voice simultaneously) 2. Internet Enabled TV; allows you to search the web and check your e- mail while watching TV.

20. 3. Virtual Reality; allows you to interact with artificial objects and environments through three dimensional computer simulation. 4. Bluetooth; a standard wireless technology that is designed to connect mobile phones, computers and other devices replacing direct cable links. … New Technologies

21. A Simple Guide to Internet Research By Greg Spence By Greg Spence

22. Finding Information Tools available: 1. Search engines. 2. Directories. 3. Meta directories. 4. E-mail.

23. Search engines A search engine is simply a database containing thousands of links to websites.A search engine is simply a database containing thousands of links to websites. There are over 2500 search engines. There are over 2500 search engines. They vary according to the type of websites they index. They vary according to the type of websites they index.

24. AltaVista; www.altavista.com AltaVista; www.altavista.comwww.altavista.com Excite; www.excite.com Excite; www.excite.comwww.excite.com Northern Light; www.northernlight.com Northern Light; www.northernlight.com www.northernlight.com Hotbot; www.hotbot.com Hotbot; www.hotbot.comwww.hotbot.com Go; www.go.com Go; www.go.comwww.go.com Google; www.google.com Google; www.google.comwww.google.com … Search engines

25. Directories A directory groups the links to indexed sites into categories. A directory groups the links to indexed sites into categories. Yahoo; www.yahoo.com Yahoo; www.yahoo.comwww.yahoo.com

26. Meta Directories A meta directory allows you to research multiple search engines and directories from one place. A meta directory allows you to research multiple search engines and directories from one place. MetaCrawler; www.metacrawler.com MetaCrawler; www.metacrawler.com

27. E-mail Before the existence of web browsers, specific programs were used to obtain research documents through e-mail. Before the existence of web browsers, specific programs were used to obtain research documents through e-mail.

28. The Right Tool for the Job?!! Excite and Google are the best tools if you are searching a concept. Excite and Google are the best tools if you are searching a concept. Meta search engines are suitable if you are just learning about a subject. Meta search engines are suitable if you are just learning about a subject. Specialty Directories are useful for broad based subjects. Specialty Directories are useful for broad based subjects.

29. Directories will do an excellent job in researching current events, finding product information, locating background information for a book, www.looksmart.com. Directories will do an excellent job in researching current events, finding product information, locating background information for a book, www.looksmart.com.www.looksmart.com Search engines are recommended for academic fields, www.northernlight.com. Search engines are recommended for academic fields, www.northernlight.com.www.northernlight.com … The Right Tool for the Job?!!

30. Interactive web search wizards can guide the researcher to the appropriate search engine or directory based on one of several predefined categories, websearch.about.com/internet/w ebsearch/library/searchwiz/bl_se archwiz.htm. Interactive web search wizards can guide the researcher to the appropriate search engine or directory based on one of several predefined categories, websearch.about.com/internet/w ebsearch/library/searchwiz/bl_se archwiz.htm. … The Right Tool for the Job?!!

31. Smartborg is a helpful tool, it analysis your key words or phrase and then suggest the search engine that will return the most relevant results, www.teleport.com/~lensman/sb/. Smartborg is a helpful tool, it analysis your key words or phrase and then suggest the search engine that will return the most relevant results, www.teleport.com/~lensman/sb/. www.teleport.com/~lensman/sb/ … The Right Tool for the Job?!!

32. How to use the major search engines for research? Alta Vista; www.altavista.com Alta Vista; www.altavista.comwww.altavista.com Excite; www.excite.com Excite; www.excite.comwww.excite.com Northern Light; www.northernlihgt.com Northern Light; www.northernlihgt.com www.northernlihgt.com Hotbot; www.hotbot,lycos.com Hotbot; www.hotbot,lycos.comwww.hotbot,lycos.com Go; www.go.com Go; www.go.comwww.go.com Google; www.google.com Google; www.google.comwww.google.com

33. Alta Vista; www.altavista.com Alta Vista; www.altavista.com www.altavista.com It indexes around 10 million web pages web pages a day. It indexes around 10 million web pages web pages a day. It finds actual words and pages from within the text of each web page. It finds actual words and pages from within the text of each web page. Boolean operators used; Boolean operators used;  AND (when you want all keywords in the search phrase to appear)  OR (when you want either keywords in the search phrase to appear)  NOT (exclude keywords in the search phrase)  NEAR (when you want each keyword in the search phrase to be within ten words from the other)

34. … Alta Vista Wildcards; AltaVista recognizes the (*) as a wildcard which is a special character that will match any letter, number or special character. Wildcards; AltaVista recognizes the (*) as a wildcard which is a special character that will match any letter, number or special character.

35. Excite; www.excite.com www.excite.com It is best designed when searching for information on a specific company and background material about that company. It is best designed when searching for information on a specific company and background material about that company. It also useful in concept searches. It also useful in concept searches. It returns real-time data with the most current information.It returns real-time data with the most current information.

36. … Excite Boolean operators used; Boolean operators used;  AND (when you want all keywords in the search phrase to appear)  OR (when you want either keywords in the search phrase to appear)  NOT (exclude keywords in the search phrase)

37. Northern Light; www.northernlihgt.com www.northernlihgt.com It is very strong at supplying newspaper and magazine stories. It is very strong at supplying newspaper and magazine stories. It returns its results in groups by category. It returns its results in groups by category. Boolean operators used; Boolean operators used;  AND (when you want all keywords in the search phrase to appear)  OR (when you want either keywords in the search phrase to appear)  NOT (exclude keywords in the search phrase)

38. … Northern Light; Wildcards; it recognizes the (*) as a wildcard which is a special character that will match any letter, number or special character. Wildcards; it recognizes the (*) as a wildcard which is a special character that will match any letter, number or special character. It also recognizes (%) which only matches a single character. It also recognizes (%) which only matches a single character.

39. HotBot; www.hotbot,lycos.com www.hotbot,lycos.com It provides focused resources that allow you to quickly find resources in a specific subject area. It provides focused resources that allow you to quickly find resources in a specific subject area. It allows you to specify how your searches should be interpreted by selecting options from the search boxes; It allows you to specify how your searches should be interpreted by selecting options from the search boxes;  all the words  any of the words  exact phrase  the page title  the person  links to this URL  the person  links to this URL

40. … HotBot Boolean operators used;Boolean operators used;  AND (when you want all keywords in the search phrase to appear)  OR (when you want either keywords in the search phrase to appear)  NOT (exclude keywords in the search phrase) Wildcards; it recognizes the (*) as a wildcard which is a special character that will match any letter, number or special character. Wildcards; it recognizes the (*) as a wildcard which is a special character that will match any letter, number or special character. It also recognizes (?) which only matches a single character. It also recognizes (?) which only matches a single character.

41. Go; www.go.com www.go.com It grades the sites as Best Sites, Very good sites and good sites. It grades the sites as Best Sites, Very good sites and good sites. You can not use Boolean operators hear, instead you use (+) or (-) signs. You can not use Boolean operators hear, instead you use (+) or (-) signs.

42. Google; www.google.com www.google.com It claims to have features that make the results returned from the search more relevant. It claims to have features that make the results returned from the search more relevant. the closer together the words in your search phrase, the higher the document is ranked in the search results. the closer together the words in your search phrase, the higher the document is ranked in the search results.

43. … Google Boolean operators used; Boolean operators used;  AND (when you want all keywords in the search phrase to appear)  OR (when you want either keywords in the search phrase to appear)  NOT (exclude keywords in the search phrase)

44. How to use subject specific search engines and directories? They are useful when searching general topics, looking for links to specialty databases, trying to find product information or trying to find other subject-based directories and websites. They are useful when searching general topics, looking for links to specialty databases, trying to find product information or trying to find other subject-based directories and websites. It is recommended to use them when you wish to find out what type of resources are available online that cover your topic It is recommended to use them when you wish to find out what type of resources are available online that cover your topic

45. How to find them? The most popular directory; Yahoo at www.yahoo.com The most popular directory; Yahoo at www.yahoo.comwww.yahoo.com A scholarly collection of internet resources; INFOMINE at lib- www.ucr.edu/main.html A scholarly collection of internet resources; INFOMINE at lib- www.ucr.edu/main.html Britannica ’ s internet guide; eBLAST at www.eblast.com Britannica ’ s internet guide; eBLAST at www.eblast.comwww.eblast.com A good tool to find more subject directories; The Internet Sleuth at www.isleuth.com A good tool to find more subject directories; The Internet Sleuth at www.isleuth.com www.isleuth.com

46. … How to find them? Strong in politics, academic resources and other general topics; Argus Clearinghouse at www.clearinghouse.com Strong in politics, academic resources and other general topics; Argus Clearinghouse at www.clearinghouse.com www.clearinghouse.com Look Smart at www.looksmart.com Look Smart at www.looksmart.comwww.looksmart.com Magellan Internet Guide at www.mckinley.com Magellan Internet Guide at www.mckinley.com www.mckinley.com Covers hundreds of subject areas and very high quality, About.com at www.about.com Covers hundreds of subject areas and very high quality, About.com at www.about.com

47. … How to find them? WebCrawler at www.webcrawler.com WebCrawler at www.webcrawler.comwww.webcrawler.com A gateway to academic resources on the web, AlphaSearch at, www.calvin.edu/library/as A gateway to academic resources on the web, AlphaSearch at, www.calvin.edu/library/as www.calvin.edu/library/as A directory of subject directories; Direct Search at gwis2.circ.gwu.edu/~gprice/direct.htm A directory of subject directories; Direct Search at gwis2.circ.gwu.edu/~gprice/direct.htm Geared towards academic resources and maintained by professional librarians; Librarian’s Index to the Internet at sunsite.berkeley.edu/internetindex Geared towards academic resources and maintained by professional librarians; Librarian’s Index to the Internet at sunsite.berkeley.edu/internetindex Open Directory Project at www.dmoz.orgOpen Directory Project at www.dmoz.orgwww.dmoz.org

48. Where can you find Meta tools? All in One at www.allonesearch.com All in One at www.allonesearch.comwww.allonesearch.com Beaucoup at www.beaucoup.com Beaucoup at www.beaucoup.comwww.beaucoup.com Dogpile at www.dogpile.com Dogpile at www.dogpile.comwww.dogpile.com Inference Find at www.infind.com Inference Find at www.infind.comwww.infind.com ProFusion at www.profusion.com ProFusion at www.profusion.comwww.profusion.com SavvySearch at www.savvysearch.com/searchSavvySearch at www.savvysearch.com/search www.savvysearch.com/search Ixquick at www.ixquick.com Ixquick at www.ixquick.comwww.ixquick.com

49. Using Natural Language You can frame your search subject in a question form and the search tool will recognize the most relevant subjects to the question you framed. You can frame your search subject in a question form and the search tool will recognize the most relevant subjects to the question you framed. Ask Jeeves at www.ask.com Ask Jeeves at www.ask.comwww.ask.com Simpli at www.simpli.com Simpli at www.simpli.comwww.simpli.com

50. Hidden Resources Websites that require a username and password to access are not available through search tools. Websites that require a username and password to access are not available through search tools. Websites that store their data in databases are not available for search robots to locate. Websites that store their data in databases are not available for search robots to locate.

51. How can we reach these hidden resources? Direct Search at gwis2.circ.gwu.edu/~gprice/direct.ht m Direct Search at gwis2.circ.gwu.edu/~gprice/direct.ht m Lycos at dir.lycos.com/reference/Searchable_D atabases/ Lycos at dir.lycos.com/reference/Searchable_D atabases/ Infomine at infomine.ucr.edu/search.phtmlInfomine at infomine.ucr.edu/search.phtml IntelliSeek at www.invisiweb.com IntelliSeek at www.invisiweb.comwww.invisiweb.com

52. Using e-mail as an Internet tool You need to send an e-mail containing the search commands to an e-mail address. You need to send an e-mail containing the search commands to an e-mail address. There are four free software programs that are capable of searching for websites via e-mail; Agora, GetWeb, WebMail and www4mail. There are four free software programs that are capable of searching for websites via e-mail; Agora, GetWeb, WebMail and www4mail. Table 5.1 may not be up-to-date, you can check www.geocities.com/CapitolHill/1236/ servers.html Table 5.1 may not be up-to-date, you can check www.geocities.com/CapitolHill/1236/ servers.html

53. Using Agora You need to submit the URL containing your search phrase. You need to submit the URL containing your search phrase. Keep in mind that the format is different for each search engine. Keep in mind that the format is different for each search engine. Place each command in the body of an e-mail and send it to Agora. Place each command in the body of an e-mail and send it to Agora. Consider the following examples; Consider the following examples;

54. … Using Agora To search AltaVista for example you send the following in the body of your e-mail; http://www.altavista.com/cgi- bin/query?q=%22YOUR_SEARCH_PHR ASE%22&kl=XX&pg=q&Translate=on &search.x=28&search.y=9 To search AltaVista for example you send the following in the body of your e-mail; http://www.altavista.com/cgi- bin/query?q=%22YOUR_SEARCH_PHR ASE%22&kl=XX&pg=q&Translate=on &search.x=28&search.y=9http://www.altavista.com/cgi- bin/query?q=%22YOUR_SEARCH_PHR ASE%22&kl=XX&pg=q&Translate=on &search.x=28&search.y=9http://www.altavista.com/cgi- bin/query?q=%22YOUR_SEARCH_PHR ASE%22&kl=XX&pg=q&Translate=on &search.x=28&search.y=9 See handout for searching other engines. See handout for searching other engines.

55. Using GetWeb You simply send in the body of your e-mail message; You simply send in the body of your e-mail message; SEARCH ALTAVISTA your_search_phrase

56. What is a Bot?! It is short for robot. It is short for robot. You can also call it an intelligent agent that can help with allsorts of mundane online tasks. You can also call it an intelligent agent that can help with allsorts of mundane online tasks. We are interested in bots that can monitor online resources and e-mail us when any changes or additions are made. We are interested in bots that can monitor online resources and e-mail us when any changes or additions are made.

57. Making the Best out of it Specify your search phrase or scope. Specify your search phrase or scope. Do not set a lot of auto searches. Do not set a lot of auto searches. Switch off the Bot when your on vacation. Switch off the Bot when your on vacation.

58. Some useful Bots The Informant at informant.dartmouth.edu The Informant at informant.dartmouth.edu TracerLock at www.peacefire.org/tracerlock/ TracerLock at www.peacefire.org/tracerlock/ www.peacefire.org/tracerlock/ Mind-it at www.netmind.com/html/url- minder.html Mind-it at www.netmind.com/html/url- minder.html www.netmind.com/html/url- minder.html www.netmind.com/html/url- minder.html