Lesson Four

1
Lesson Four

• Searching Effectively on the
• World Wide Web

2
Introduction to Search Tools

• Before starting this section, it is best to be
  familiar with terms related to the Internet and
  World Wide Web (WWW).
• This lesson will focus on how to search the World
  Wide Web effectively and efficiently.

3
Introduction to Search Tools

• Search Tools
• There are many type of search tools that you can
  use to locate information on the World Wide Web.
• Various search tools are developed by different
  companies and have different search features and
  techniques.
• They search different and overlapping parts of
  the WWW.

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Introduction to Search Tools

• NO single search tool searches ALL of the web
  sites (there are millions of web sites and more
  are added each and every day).
• The search tools include
• Search engines
• Web subject directories
• Metasearch engines
• the Invisible Web (also known as the "Deep Web")

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Comparison of Different Search Tools Search
Engines

• Definition
• Databases that contain millions and millions of
  pages.
• Automated software ("robots" or "spiders") scan
  the Internet and collect information.
• The search engine interface allows you to search
  for certain words or phrases found on Web pages.
• In a search engine, you are searching for
  information within that search engine only, not
  the entire WWW.

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Comparison of Different Search Tools Search
Engines

• Advantages
• Search engines contain millions of web pages.
• You retrieve results that match the word(s) that
  you are looking for.
• Can be useful for searching for unique or
  specific topics.

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Comparison of Different Search Tools Search
Engines

• Disadvantages
• Depending on the search engine, you may get
  thousands or millions of results.
• Many of the results may not be exactly what you
  are looking for, especially if you are using
  broad or common terms.

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Comparison of Different Search Tools Search
Engines

• Examples
• AltaVista (http//www.altavista.com)
• Lycos (http//www.lycos.com)
• Google (http//www.google.com)

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Comparison of Different Search Tools Web Subject
Directories

• Definition
• A collection of web sites gathered by the
  creators of the directory or submitted by
  publishers of web sites.
• People evaluate and classify the web sites that
  are placed in the directory.
• There may be short summaries that describe the
  web sites in the directory.

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Comparison of Different Search Tools Web Subject
Directories

• Advantages
• There may be a higher degree of accuracy using
  web directories for researching broad subjects or
  topics.

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Comparison of Different Search Tools Web Subject
Directories

• Disadvantages
• Usually fewer web sites than a search engine.
• Web directories may not be as useful as search
  engines for researching specific or obscure
  topics.

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Comparison of Different Search Tools Web Subject
Directories

• Examples
• Yahoo! (http//www.yahoo.com)

13
Comparison of Different Search Tools Metasearch
Engines

• Definition
• Similar to search engines but are used to search
  more than one search engine at a time.
• Some Metasearch engines will also show you a
  small number of the "best" web sites from each
  search engine based on criteria established by
  the metasearch engine.

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Comparison of Different Search Tools Metasearch
Engines

• Advantages
• You can search several search engines at one
  time.

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Comparison of Different Search Tools Metasearch
Engines

• Disadvantages
• You may retrieve inappropriate Web sites
  depending on how each individual search engine
  interprets the search.

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Comparison of Different Search Tools Metasearch
Engines

• Examples
• Dogpile (http//www.dogpile.com)

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Comparison of Different Search Tools Invisible
Web

• Definition
• Web sites that are hidden from use by the general
  public. Also known as the Deep Web.
• Includes specialized databases and directories.

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Comparison of Different Search Tools Invisible
Web

• Advantages
• Can be useful for specific topics or unique
  terms.

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Comparison of Different Search Tools Invisible
Web

• Disadvantages
• The Invisible Web will not be located by the use
  of conventional search engines and directories.
  You must know the URL or search using a search
  tool specifically created for searching parts of
  the Invisible Web.

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Comparison of Different Search Tools Invisible
Web

• Examples
• Complete Planet (http//www.completeplanet.com)

21
The Differences Between Search Tools

• To demonstrate the differences between the four
  types of search tools, please conduct the
  following search using these four search tools
• Google (Search Engine)
• Yahoo! (Web Directory)
• Dogpile (Metasearch Engine)
• Complete Planet (Invisible Web)

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The Differences Between Search Tools

• To start, open Google (http//www.google.com) in
  a new browser window. Perform a search for the
  psychologist Joyce Brothers.
• How many results (hits) did you retrieve?

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The Differences Between Search Tools

• Now, search Yahoo! (http//www.yahoo.com).
• Scroll down to the Web Site Directory section
  (sites organized by subject).
• Click on Psychology (found under Social
  Sciences).
• Click on Psychologists.
• Click on Joyce Brothers.
• How many results (hits) did you retrieve?

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The Differences Between Search Tools

• Now, search Dogpile (http//www.dogpile.com). "Go
  Fetch" Joyce Brothers!
• How many results (hits) did you retrieve?

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The Differences Between Search Tools

• Finally, search Complete Planet
  (http//www.completeplanet.com). "Find databases
  relevant to" Joyce Brothers.
• How many results (hits) did you retrieve?

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The Differences Between Search Tools

• As you can see from the searches above, you
  retrieve a variety of results using the different
  search tools.
• Which search tool did you like the best?
• The search engines may not be as precise ("on
  target") as some of the other search tools but
  retrieve a large number of results.

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Before Starting a Search...

• Before beginning a search, think about what you
  are looking for.

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Effective Searching

• Once you have decided on a search strategy, enter
  your search.

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Limitations of the World Wide Web

• It is important to realize that even the most
  effective Web searches will often turn up useless
  results (or no results at all).
• Though the Web can be a wonderful search tool for
  current, "cutting-edge" information, there are
  limitations that can hinder a Web search.
• What are some of these limitations?

30
A Limitation of the Web

• Contrary to popular belief, everything cannot be
  found on the web.
• There are millions and millions of documents
  written prior to the creation of the Internet.
• Older, historical documents, in particular, may
  not have been digitalized and placed on the Web.
• Most of what can be found on the Web is
  information that was developed after the creation
  and wide-spread use of the Web.

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A Limitation of the Web

• Not everything is free on the Web.
• Some fee-based Web sites may require monthly or
  yearly subscriptions.
• This includes many of the electronic databases.
  You (or your institution) pays for the privilege
  of accessing the information on those databases.

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A Limitation of the Web

• Web pages can be updated, redesigned, or removed.
• Have you ever found a great Web page, just to
  find out that it can no longer be found two weeks
  later?
• This is due to the fact that items on the
  Internet are not in a permanent format.
• The Web address of a Web page can change.
• The author of a Web page may decide to remove it
  from the Internet.

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A Limitation of the Web

• Anyone can publish web pages on the Internet.
• All web pages are not "created equal." Becoming a
  web author is as easy as having access to the
  Internet and some web-building software.
• Some of these "authors" may publish inaccurate or
  hurtful information.
• It may be hard to verify the credibility of
  information on the WWW.

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Using the Web for Research

• Often, the Web may not be the best place to start
  your research.
• You may instead choose to
• Review encyclopedias and reference books for
  background information.
• Look at journal or magazine articles related to
  the topic.
• Then... look for Web sites to supplement or
  update your information.

35
Evaluating a Web Site

• As stated earlier, anyone can publish on the Web.
  
• The author of a Web page may be opinionated or
  incorrect about the facts.
• It is very important to look at a Web site
  thoroughly to make sure that it contains accurate
  and reliable information.

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Take a Look at These Web Sites!

• Below are the links to several Web sites.
• Please take a look at these and determine whether
  the Web sites are credible and reliable sources
  of information.

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Take a Look at These Web Sites!

• Which of these sites are credible?
• Dangers of Bread
• National Aeronautics and Space Administration
• Prehistoric Archaeology of the Aegean
• Portland Online
• Republic of Molossia
• Smithsonian Institution

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Take a Look at These Web Sites!

• Dangers of Bread is NOT a valid Web site.
• The National Aeronautics and Space Administration
  IS a valid Web site.
• The Prehistoric Archaeology of the Aegean IS a
  valid Web site.
• Portland Online IS a valid Web site.
• The Republic of Molossia is NOT a valid Web site.
• The Smithsonian Institution IS a valid Web site.

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Take a Look at These Web Sites!

• How did you do?
• Sometimes it is easy to know that a Web site is
  not credible, at other times it is very
  difficult.

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For More Information About Searching Effectively
on the World Wide Web...

• Here are some Web sites that provide additional
  information.
• Five Criteria for Evaluating Web Pages
  (http//www.library.cornell.edu/olinuris/ref/resea
  rch/webcrit.html) is a Web site developed by the
  Olin and Uris Libraries at Cornell University.
• Noodle Tools Search Strategies - Choose the Best
  Search for Your Information Need is an excellent
  source that describes the type of search tools
  that may work best for various topics. This Web
  site can be found at (http//www.noodletools.com/d
  ebbie/literacies/information/5locate/adviceengine.
  html).
• ICYouSee A Guide to Critical Thinking About What
  You See on the Web contains useful advice on how
  to access and evaluate resources. This Web site
  is developed by the Ithaca College
  Library.(http//www.ithaca.edu/library/training/th
  ink.html).