Information on the Internet

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Information on the Internet
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http

• hypertext transfer protocol
• Web clients (browsers) make request to the web
  server.
• Looks for web page written in HTML.

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URL

• Uniform Resource Locator
• Entire location of a page/image
• http//www.amazon.comhttp//keep3.sjfc.edu/facult
  y/jsarachanhttp//www.amazon.com/exec/obidos/sear
  ch-handle-form/102-3711441-9976104http//www.sjfc
  .edu/admissions/academics.asphttp//www.hammersaw
  .com/logo.gif

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Parts of a Domain Name

• Top Level (TLD).com, .edu, .net, .gov, .org,
  .biz, .info.ca, .uk, .tv
• Second Level
• Third Level (www)

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IP Address/Domain Name System

• IP Address has 4 parts 64.236.16.20
•  D omain name system links URL to IP address via
  DNS servers
• DNSDomain Name System
•  Static vs. Dynamic IP addresses

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How Search Engines Work I

• A search engine uses a form of software that can
  travel on the web called a crawler or spider
  or bot.
• Examines each page, and each link (some ignore
  images, pdf files, etc.).
• Information about each page (everything or
  headings, keywords) are sent back to database.
• Webmasters can submit site to speed up process.

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How Search Engines Work II

• User submits keywords that match keywords from
  the site, as well as dates created or other
  criteria.
• Information from database is returned, ordered by
  different rules (relevance, age).
• User may be given title and URL and/or sentences
  about document (meta tags).

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Optimization of Web Sites

• Web Designers should pick obvious names for the
  URLwithout hypens or misspellings.
• Use meta tags.
• Frequency of keywords on page.

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Finding Web Sites

• Use different rules (algorithms) to organize web
  pages.
• Keyword frequency/placement/prominence
• Fuzzy search
• Relevance (order of keywords matter)
• Site popularity
• Paying for Placement
• Boolean logic

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Two type of search sites

• Directories (indexes)
• Search Engines

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Google

• http//www.google.com
• Works as phone bookcombination of first and
  last name, city, stateOR phone number
• Finds street maps via yahoo or mapquest
• Dictionary definitions
• Stock quotes (to yahoo)

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Typical Rules

• spider man (include whole phrase)
• Spider -man (dont include this word)
• Spider ANDNOT man(dont include second word)
• (spider man) (one word or the other)
• Spider OR man (one word or the other)
• spider man (both spider and man)
• Spider AND man (both spider and man)

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Searching Extras

• Google
• biology sitewww.sjfc.edu
• linkwww.sjfc.edu
• Infowww.sjfc.edu
• Advanced Search (and tips) in Google

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Other search engines

• www.yahoo.com
• www.findarticles.com
• www.dogpile.com
• www.askjeeves.com
• www.beaucoup.com (free information)
• www.kartoo.com
• www.archive.org

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Things You Can Find on the Internet

• Websites
• Images
• MP3 files
• News
• Maps/directions (www.mapquest.com)
• People(www.switchboard.com,whitepages.com,yahoo.c
  om)
• Games (www.gamespot.com)
• Film or TV show information (www.imdb.com)
• Music Information (www.allmusic.com)
• Lyrics (type into Google)
• Health Information (www.webmd.com)

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Bookmarks

• Also called Favorites
• In IE, if you are on a page you want to keep,
  choose Add Page to Favorites
• You can organize favorites and add URLs to
  toolbar.