The Web by chenmeixiu

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									Computers, The Internet
     & The Web

        M. Jacie Yang
    Texas State University
Computers
                Computers
• Hardware
  – Motherboard
  – CPU (Central Processing Unit)
  – RAM (Random Access Memory)
  – Hard drive
  – CD/DVD drive
  – Power
• Operating Systems
• Software
            Operating Systems
• Windows (PC)
  – Windows XP
  – Windows Vista
  – Windows 7
• Mac OS
  – Classic Mac OS
  – Mac OS X
• Linux

• OS Market Share
                    Display
• Pixel
  – Smallest addressable screen element
  – Also a unit for image dimensions
• Screen display
  – Lower than 1024x768
  – 1024x768
  – Higher than 1024x768
  – Screen display market share
                      Files
• File size
   – 1 bit= 0 or 1
   – 1 byte= 8 bits
   – 1KB= 1024 bytes (1024=210)
   – 1MB= 1024KM
   – 1GB= 1024MB
   – 1TB= 1024GB
• So, do you need a 32G ($299) iPod or a 64G
  ($399) iPod?
Internet=Web?
The Internet
         Defining the Internet
• The Internet is a global system of
  interconnected computer networks that use
  the standard Internet Protocol Suite (TCP/IP)
  to serve billions of users worldwide
  (Wikipedia).
• An electronic communications network that
  connects computer networks and
  organizational computer facilities around the
  world (Merriam-Webster).
        History of the Internet
• History of the Internet
• In the 1960s (the Cold War)
• US government created Defense of Advanced
  Research Projects Agency (DARPA)
• US Military was concerned about survivability
  of their centralized communication networks
• First two nodes of the ARPANET
  – UCLA, School of Engineering & Applied Science
  – SRI International in Menlo Park CA
What Can You Do on the Internet?
•   E-Mail (electronic mail)
•   Instant Message (AOL, MSN Messenger, etc)
•   BBS (Bulletin Board System)
•   VOIP (Voice-over Internet Protocol)
•   WebCam
•   File sharing (FTP)
•   Media Streaming (webcasts, podcasting)
•   The Web
The Web
           Defining the Web
• The Web: World Wide Web, or WWW.
• A system of interlinked hypertext documents
  accessed via the Internet (Wikipedia).
• A part of the Internet accessed through a
  graphical user interface and containing
  documents often connected by hyperlinks —
  called also Web (Merriam-Webster).
            History of the Web
• 1989-1990
• Tim Berners-Lee
• Built “Hypertext project”
  called WorldWideWeb.
• Creator of HTML
  (Hypertext Markup
  Language).
      Mosaic: First Web Browser
• 1992-1993
• Made the Web
  popular and
  accessible to the
  public.
• Later become
  Netscape (1994).
                Web Browsers
•   Internet Explorer (Microsoft, 1995)
•   Opera (Opera Software,1996)
•   Firefox (Mozilla Corporation, 2004)
•   Safari (Apple, 2005)
•   Chrome (Google, 2008)

• Browsers Market Share
       How to Locate Web Sites?
• URL: Uniform Resource Locator
   – i.e. http://www.txstate.edu
• http://
   – Hypertext Transfer Protocol
• www
   – World Wide Web
• www.txstat.edu
   – Domain name
                  Example of URLs
• URL:
   – http://www.txstate.edu
   – ftp://admin@ftp.jacieyang.com
   – http://en.wikipedia.org/wiki/Uniform_Resource_Locator

• Domains:
   – www.txstat.edu
   – www.jacieyang.com
• Subdomains:
   – www.masscomm.txstate.edu/
   – www.library.txstate.edu/
   – www.wcms.jacieyang.com
       How does the Web work?
• How does the Web work?
• WWW in Plain English
        Multimedia on the Web
•   Text
•   Images
•   Audio
•   Video

• Let’s take a look at those elements on the
  Web.
            Images on the Web
• JPG/JPEG (Joint Photographic Experts Group)
  – Supports true color
  – Is usually the file format of digital cameras
• GIF (Graphic Interchange Format)
  – 256 colors
  – Good for graphics with limited colors
• PNG (Portable Network Graphics)
  – Best when you have combination of photos and
    text
    Audio and Video on the Web
• Popular audio formats:
  – MP3, ACC, WMA
• Popular video formats:
  – AIFF, WAV, MOV (QuickTime), MP4, RM
• Supports both audio and video:
  – ogg
Search Engines
        Defining Search Engines
• A web search engine is designed to search for
  information on the World Wide Web
  (Wikipedia).
• Computer software used to search data (as
  text or a database) for specified information;
  also : a site on the World Wide Web that uses
  such software to locate key words in other
  sites (Merriam-Webster).
  How Do Search Engines Work?
• How Search Engines Work
        Popular Search Engines
• Search Engines
  – Google
  – Bing
  – Yahoo
  – Ask.com
• Meta-search engines
  – Ixquick
  – Clusty
Building a Web Site
    Static & Dynamic Web Pages
• Static Web pages:
  – HTML documents stored on Web servers.
  – The content of the page does not change in
    response to users input.
• Dynamic Web pages:
  – A page that is generated by a server-side program
    or script.
  – The page changes accordingly to the information
    that is submitted by the browser to the server.
          Server-side Languages
•   PHP
•   JSP
•   ASP.NET
•   Perl
•   Python

								
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