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  • 1. Unit 1—Computer Basics Lesson 3 The Internet and Research
  • 2. Objectives
    • List some reasons for searching the Internet.
    • Describe different search approaches.
    • Define a search engine.
    • Explain how search engines work.
    • Identify some of the more popular search engines.
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  • 3. Objectives (cont.)
    • List some of the specialty search engines.
    • Describe some search tips and tricks.
    • Describe the subject directory search approach.
    • Describe the invisible Web.
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  • 4. Why Search the Internet?
    • Reasons that people search the Internet
      • Research for school assignments
      • Looking for medical and scientific information
      • Travel information and accommodations
      • Shopping for goods and services
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  • 5. Internet Search Tools
    • There are two basic types of Internet search tools:
      • Search engines
        • Perform searches based on keywords
      • Subject directories
        • Search by specialized topics
    • What is the difference between them?
      • Search engines are automated.
      • Directories are assembled by people.
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  • 6. What Is a Search Engine?
    • Search engines are programs that allow you to search for information.
    • There are hundreds of search engines on the Internet.
    • Search engines allow keyword searching.
      • Some support concept-based searching.
      • Some support stemming .
    • The list of results returned from your search are called hits .
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  • 7. Search Engine Components
    • Search engines usually have three main components.
      • The search engine program that does the search of its database
      • A spider or crawler that looks for the information in the database
      • The index that is built from information returned by the spider
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  • 8. Keyword Searches
    • Keyword searches look for specific words within a Web page.
    • Many search engines use meta tags to build their search index.
      • Meta tags are HTML tags in a Web page that do not display, but can be used to define page content.
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  • 9. Keyword Searches (cont.)
    • Search engines also use significant words to build their index.
      • Significant words may be words mentioned near the beginning of a page or repeated frequently throughout the page.
    • Some search engines claim to index all words in a Web page.
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  • 10. Keyword Search Steps
    • To search using keywords:
      • Connect to the Internet and go to a search engine site.
      • Enter your keywords in the search box.
        • Many search engines allow you to enter a phrase or sentence.
      • The search engine examines its internal database index looking for your words.
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  • 11. Keyword Search Steps (cont.)
    • To search using keywords (cont.):
      • The search engine returns a list of hyperlinks (hits) to Web sites containing your words.
      • Click a hyperlink to go to that site.
    • If you get no hits on your search, revise your keywords and try again.
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  • 12. Major Search Engines
    • Although there are hundreds, these are some of the more well known search engines:
      • Yahoo at
      • Microsoft at
      • America Online at
      • Ask Jeeves at
      • Netscape at
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  • 13. Specialty Search Engines
    • These also are called category-oriented search engines.
    • They are commonly used for
      • Locating people
      • Finding shareware and freeware
      • Shopping
      • Sports-related information
      • Career planning
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  • 14. A Specialty Search Web Site Computer Concepts BASICS - This figure shows the Beaucoup Web site page. Note the various categories of information available. Clicking a sub-category will bring up a new page of categories until you find the exact topic you are searching for.
  • 15. Tools and Techniques for Searching
    • Some commonly used techniques
      • Phrase searching
      • Search engine math
      • Boolean searching
      • Wildcard searching
      • Title searching
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  • 16. Phrase Searching
    • This is used to search for words that must appear next to each other.
    • Phrases must be enclosed in double quotation marks.
      • “ Books on the Civil War”
    • Only sites with the exact phrase will be returned as hits.
    • You should capitalize proper nouns.
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  • 17. Search Engine Math
    • Use math symbols to enter formulas or to filter out unwanted listings.
      • A plus sign ( + ) before a word means it must appear.
      • A minus sign ( - ) before a word means it should not appear.
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  • 18. Search Engine Math (cont.)
    • Examples of search engine math
      • To search for sites that contain both cookies and recipes, enter
        • +cookies+recipes
      • To exclude sites that have coconut cookie recipes, enter
        • +cookies+recipes-coconut
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  • 19. Boolean Searching
    • Boolean logic is similar to search engine math, but is more powerful.
    • Boolean logic consists of three operators:
      • AND: Search for sites that include Word A AND Word B.
      • NOT: Search for sites the include Word A but NOT Word B.
      • OR: Search for sites that include Word A OR Word B.
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  • 20. Wildcard Searching
    • Wildcard searching allows you to search for words for which you may not know the spelling or to search for plurals or variations of a word.
    • The wildcard character ( * ) lets you search for any word that has the characters before or after the wildcard character.
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  • 21. Wildcard Searching (cont.)
    • Wildcard search example
      • To search for the element potassium without knowing how it is spelled, enter
        • PO* or po*ium
    • Not all search engines support wildcard searches.
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  • 22. Related Searching
    • Some search engines have a related search feature.
    • The search engine will return hits based on your search criteria and may also display a list of other sites that have information related to your search criteria.
    • This can greatly improve the odds of finding the information that you want.
    • Note: Some sites call this feature similar pages or more pages like this .
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  • 23. Subject Directory Searching
    • Subject experts personally examine Web sites and add the URL to a search engine if it meets standards.
    • Subject directories are organized by subject categories.
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  • 24. Subject Directory Searching (cont.)
    • Subject categories
      • Each category has a collection of links to Internet resources.
      • The resources are arranged by subject and displayed in menus.
    • You start at the top of a category and drill down from a generic start to a specific topic.
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  • 25. A Subject Directory Site Computer Concepts BASICS - This figure shows the Yahoo Subject Web site.
  • 26. Advantages of Subject Directory Searches
    • They usually provide a more guided approach than keyword searches.
    • They are easy to use.
    • You are not searching the entire Web.
    • The linked sites have been handpicked and evaluated.
    • Most links include a description.
    • They produce better quality hits on searches for common items.
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  • 27. Popular Subject Search Sites
    • About:
    • The Librarians Index:
    • Yahoo:
    • Galaxy:
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  • 28. Advanced Search Forms Computer Concepts BASICS - This figure shows the advanced search form for the AltaVista Web site. It is designed to assist you in performing advanced searches by providing text box options.
  • 29. The Invisible Web
    • Also known as the “deep Web”
      • Indexes searchable databases
    • Resources
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  • 30. Summary
    • Search engines and directories are two basic tools that you can use to find information on the Web.
    • People assemble directories; search engines are automated.
    • A search engine is a software program.
    • Most search engines support keyword searches.
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  • 31. Summary (cont.)
    • Concept-based searching occurs when the search engine returns hits that relate to keywords.
    • Stemming relates to the search engine’s capability to find variations of a word.
    • Meta tags are special tags embedded in a Web page; many search engines use the tags to create their indexes.
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  • 32. Summary (cont.)
    • Keywords describe the information you are trying to locate.
    • Search engines contain a database of organized information.
    • Some search engines use natural language.
    • A search engine has three main parts: the search engine software, a spider that searches for keywords, and an index.
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  • 33. Summary (cont.)
    • Stop words, such as www , but , and or , are not indexed by many search engines.
    • A search engine uses an algorithm to index Web sites.
    • Specialized search engines focus on a particular topic.
    • Multimedia search engines focus on video, animation, graphics, and music.
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  • 34. Summary (cont.)
    • Subject directories are organized by subject categories.
    • Subject experts check the Web sites that are part of a subject directory’s database.
    • Use double quotation marks around a set of words for phrase searching.
    • Use the plus and minus signs for inclusion and exclusion of words within a search.
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  • 35. Summary (cont.)
    • Boolean searching uses the three logical operators OR, AND, and NOT.
    • The * symbol is used for wildcard searching.
    • No single organization indexes the entire Internet.
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