Introduction to the World Wide Web

Document Sample
Introduction to the World Wide Web Powered By Docstoc
					Introduction to the World Wide
              Web
        The Padnos School
What is the World Wide Web?
• The WWW is the newest way to access information
  across the Internet.
• It was developed in the early 1990’s in Switzerland at
  CERN (the European Particle Physics Laboratory) to
  facilitate communication between scientists.
• It provides a consistent interface to many different
  types of information—text, images, video and audio—
  from many different sources, including educational
  and commercial institutions.
        Why is the Web cool?
• Embedded in every Web document are hypertext
  links, which allow you to jump between documents.
  By following these links you can access information
  from all over the world.
• The Web is a multimedia experience, incorporating
  text, images, video and audio.
• It integrates many of the other tools of the Internet
  including telnet, ftp, gopher, WAIS and news.
  Accessing these resources is no different from
  following any other Web link.
     Some helpful acronyms
• HTTP—HyperText Transfer Protocol. The protocol
  that allows Web clients (browsers) and servers to
  communicate.
• HTML—HyperText Markup Language. The language
  used to write Web documents that defines how the
  document will be displayed and specifies the
  hypertext links.
• URL—Uniform Resource Locator. The ―address‖ of a
  resource on the Web.
               More on URL’s
• A URL consists of four main parts:
   – the protocol—the method used to send or retrieve data.
   – the host—the computer host where the resource is located.
   – the port—a number identifying the service you are
     requesting from the computer host.
   – the path—the full pathname which identifies the location of
     the resource in the host’s directory structure.
• Important: URL’s must be typed exactly as shown—
  upper- and lowercase are significant.
                    Browsers
• Browsers or clients are the computer programs used
  to access the Web.
• Commonly used browsers are:
   – Internet Explorer—available on Windows.
   – Netscape—available on Macintosh, Windows, and UNIX.
• Older browsers are:
   – NCSA Mosaic—available on Macintosh, Windows, and
     UNIX.
   – Lynx—available on VMS and UNIX.
      Graphical vs. Text-only
            Browsers
• Internet Explorer, Netscape and Mosaic are graphical
  browsers.
• Lynx is an example of a text-only browser.
• Graphical browsers allow you to access all of the
  multimedia features of the Web, including text,
  images, video and audio.
• Text-only browsers can only display text. Images are
  not displayed.
             Internet Explorer
• Internet Explorer commands are available both from
  the menu bar and from buttons located at the top of
  the page.
• Some useful commands:
   – File/Open Location—brings up a dialog box where you can
     enter a URL.
   – View/Go to/Forward and Go/Back (Forward and Back
     buttons)—move forwards and backwards along the links you
     have have been to.
   – View/Go to /Home (Home button)—jump to your default
     home page.
   Internet Explorer (con’t)
– File/Print (Print button)—print the page you are currently
  viewing.
– Favorites/Add—add the current page to your favorite
  bookmarks file. Once you have added a Web page to your
  bookmarks file you can jump to it directly by selecting it from
  the Bookmarks menu.
– Help—brings up Internet Explorer’s help page where you
  can find out more about how to use Internet Explorer.
– File/Quit—quit Internet Explorer.
                    Netscape
• Netscape commands are available both from the
  menu bar and from buttons located at the top of the
  page.
• Some useful commands:
   – File/Open Location (Open button)—brings up a dialog box
     where you can enter a URL.
   – Go/Forward and Go/Back (Forward and Back buttons)—
     move forwards and backwards along the links you have
     have been to.
   – Go/Home (Home button)—jump to your default home page.
           Netscape (con’t)
– File/Print (Print button)—print the page you are currently
  viewing.
– Bookmarks/Add—add the current page to your bookmarks
  file. Once you have added a Web page to your bookmarks
  file you can jump to it directly by selecting it from the
  Bookmarks menu.
– Help/Handbook (Handbook button)—brings up Netscape’s
  help page where you can find out more about how to use
  Netscape.
– File/Quit—quit Netscape.
              Where to Start
                  Directories
• GVSU: http://www.gvsu.edu/
• Yahoo: http://www.yahoo.com/
• The Whole Internet Catalog:
  http://nearnet.gnn.com/wic/
• The WWW Virtual Library:
  http://www.w3.org/hypertext/
  DataSources/bySubject/Overview.html
• U.S. Geological Survey Network Resources: http://
  www.usgs.gov/network/index.html
• EINet Galaxy:
  http://www.usgs.gov/network/index.html
             Where to Start
              Search Engines
• Yahoo search: http://www.yahoo.com/search.html
• Lycos: http://lycos.cs.cmu.edu/
• Webcrawler searching:
  http://webcrawler.cs.washington.edu/WebCrawler/
  WebQuery.html
• World Wide Web Worm:
  http://www.cs.colorado.edu/home/mcbryan/WWWW.
  html
             Where to Start
                Personal Lists
• Women and Minorities in Science and Engineering:
  http://www.ai.mit.edu/people/ellens/Gender/wom_and
  _min.html
• Jon Wiederspan’s WWW developer resources:
  http://www.uwtc.washington.edu/Computing/WWW/D
  ocumentation.html
• Physics Services and Servers Around the World:
  http://www.physics.mcgill.ca/physics-
  services/physics_services2.html

				
DOCUMENT INFO