Searching the Web

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Searching the Web

• Search engines and directories
• Locating these resources
• Using these resources
• Interpreting results
• Locating specific text on a Web page
• Extras

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Challenge

• The Web contains millions of pages on just about
  any topic.
• Hundreds of new pages appear each day
• Need to sift through information
• Use the Web tools call search engines and
  directories

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Search Engines and Directories

• Are actually Web pages
• been designed for helping you find what your
  looking for
• A search engine uses a bottom-up strategy
• A directory uses a top-down approach
• A directory is also called a navigational guide

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Search Engines

• Rely on you to provide the search parameters
• begin with a specific word or phrase

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New Problem for Search Engines

• Now many pages are created dynamically how can
  you catalog these pages
• All the new multimedia formats and cataloging
  these

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Directories

• Provide a number of topics from which to choose.
• Select a top-level category and work through
  sub-menus until you find your specific
  requirements
• Great many directories, some limited to a
  particular topic, some cover the entire Internet

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Finding Search Engines

• Click the flashlight on the browsers tool bar
• In Netscape this page is called the Netscape Net
  Search page
• There are a number of search services listed on
  this page

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Using the Search Engines

• You can perform a search directly from the Net
  Search page using any of the search services
  display on the tabs.
• Alternatively, you can jump directly to the home
  page of any of these services using the links
  provided by Netscape

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Using Infoseek

• Most search engines are functionally very
  similar, so once you learned to use one, learning
  others will be a easy.
• Most search engines provide a tutorial. Infoseek
  s page has a hyperlink Tips that will help with
  the syntax used by Infoseek.

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Searching Example

• Search for job opportunities in your field
• Typed employment in the Infoseek field on the Net
  Search page.
• Hit the Seek button
• Searches for the word employment among the Web
  pages currently indexed in its database (this
  changes daily)

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Searching Example

• Generally, the header, description, and body of
  documents are searched.
• Different search engines perform the searches
  differently.
• Searches can result in hundreds or hundreds of
  thousand of hits.
• Because employment is a fairly common word -
  400,000 matches

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Searching Example

• The results page displays the first ten documents
  on that list.
• A text link near the top and bottom of search
  results pages that allows you view the next ten
  (or the previous ten).
• Percentage-based relevance ranking beside each
  hit.

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Smart Searches

• Use more search words
• Use quotes to enclose phrases
• Capitalize names and titles
• Exclude words
• Learn basic Boolean

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Use More Search Words

• Say you wanted pictures of Jupiter
• then your search words should at least include
  pictures and Jupiter
• use
• Jupiter AND planets AND pictures
• (since Jupiter was also a Roman god and want to
  eliminate these pages)

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Use Quotes to Enclose Phrases

• When you are searching for a phrase such as solar
  system, enclose the entire phrase in double (not
  single) quotation marks.
• Forces the engine to find words adjacent to each
  other.

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Capitalize Names and Titles

• When you are searching for people and places or
  titles of movies or books, capitalize them.
• Most search engines interpret capital letters as
  a request for an exact case match. Other wise
  treated like any group of words. - rock hudson
  would find rock climbing, rock music, Hudson
  river, etc.

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Exclude Words

• You can exclude a word from a query with a -
  (minus) sign or NOT command.
• A query such as cats NOT dogs, ignores pages
  where both animals are mentioned.

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Learn Basic Boolean

• A Boolean search is a query with multiple words
  separated by AND, OR and NOT.
• When entering searching such as medieval
  superstition, actually creating a Boolean query,
  since most engines invisibly add the OR operator
  as they comb their databases

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Learn Basic Boolean

• OR returns pages with either of the keywords
• And returns only those pages that include both
  keywords
• Not returns those pages that does not include the
  keyword

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A Directory Example

• Use Excite
• Excite qualifies as both a search engine and
  directory (so is Infoseek)
• looking for job opportunities
• Select Business topic
• Select Jobs from Business subtopics
• Select Job Banks from Jobs subtopics

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Searching for Text on a Web Page

• After a search and following several links, end
  up with screens full of information
• You can scroll through the entire page and skim
  the text or you can use the find tool.

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Using Find

• Click Find button (binoculars) on the browsers
  toolbar or on the Edit menu
• Type the word or phrase in the Find what text
  box.
• Click the Down radio button to search the
  document from the insertion point to the end of
  the document.
• Click the Find Next for more
• Click the Cancel to close the dialog box

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Using the History Log

• Netscape tracks the URL of every Web page you
  visit on the Go menu.
• The history log is a list of sites that you have
  visited since launching Netscape.
• From the history log you can jump to a visited
  URL.
• Easier than clicking the Back button

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Other Focused Searches

• Lycos PeopleFind
• Inside of PeopleFind, Reverse Find,
• enter a phone number, tells you who it belongs to

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Generated and Human Lists

• Those lists of massive matches are normally
  generated by a computer program. A program goes
  through the Web and determines if the words in
  your search are on a Web page.
• Yahoo works differently

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Yahoo Index

• Every Web page which is included in the Yahoo
  index is added by a human.
• Each Web pages is humanly read and classified
  under a category.
• Thus Yahoo search will be more discriminating but
  also incomplete in that the newest pages are
  probably not classified yet.

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Questions