"Hyper Text Markup Language "

	

	  
 WWW
	  
 World Wide Web 
	   
 SGML
	   
 Standard Generalized Markup Language -a standard for describing markup languages.
	   
 DTD
	   
 Document Type Definition -this is the formal specification  of a markup language, 
		     written using SGML.
	  
 HTML
          
 Hyper Text Markup Language -it is design to  be platform independent not bound to 
		     a particular hardwae or software.
        


	

 HTML Document 
	



	
	
	

	


	
	    HTML documents are plain-text (also known as ASCII) files that can be created using any text 
	    editor (Emacs or vi on Unix machines BBedit on Macintosh; Notepad on a windows machine). You can
	    also use word-processing software if you remember to save your document as "text only line breaks."
	
 HTML and the Web 
	



	
	
	

	


	
	    The lingua franca of the World Wide Web was develop in Swtzerland, which has four official state languages.
	    Perhaps acutely aware of how difficult it is for people to communicate without a common language, the programmers
	    at the CERN research lab created a kind of Esperanto for computers: the Hypertext markup Language or HTML.
	          
	    HTML allows you to format text, add rules, graphics, sounds and video and save it all in a text-only  ASCII file that
	    any computer can read.  The key to HTML  is in tags, keywords, enclosed in less than (<> and greater than(>) signs, that
	    indicate what kind of contents is coming up.
	      
	    HTML just like a lot of text sprinkled with greater than and less than signs you open the file with a special program called
	    a Browser.  A browser can interpret the HTML tags then show  the formatted document on screen.
	    
	    HTML documents can contain links to otehr HTML documents or to practically anything else on the internet.  This means that you can 
	    create several Web pages and have your users jump from one to another as needed.  You can also create links to another organizations Web
	    pages, giving your users access to information held at other sites.
	    HTML just like a lot of text sprinkled with greater than and less than signs until you open the file wiht a special program 
	    called Browser.
 Different Versions of HTML 
	    The internet is democracy in action. While the original HTML sandad was decveloped  by CERN, new versions are hashed out through a series of 
	    online meetings open to anyone on the Internet.  Then they  are analyzed, discussed, decided and published by the W3 Consortium, led by the
	    Laboratory for Computer Science at the Massachussetts Institute of Technology(MIT) and  INRIA, a French technolgy group, in collaboration with 
	    CERN.
	    At press time, although HTML 3.2 is considered the current standard, the actual guidelines had not yet been finalized.  In addition , two commercial
	    companies- NEtscape Communications ana Microsoft continue to add  features to their browsers without worrying much if these features will be supported
	    by other browsers.
 HTML Browsers 
	
	     The most important HTML tool for creating  HTML documents is HTML browser.  You might think that  only  your users need to have a browser, but you'd be 
	     wrong.  It is absolutely  vital that you have at least one, and preferably three or four of the principal browsers in use around the world.  This way you
	     can  test your HTML pages and make sure that they look the  way you want them to regradless of the browser used.
	     The two most popular browsers are Netscape  Navigator  (soon to be Communicator) and Microsoft Internet Explorer.  Both are available on a variety of 
	     platforms.
	
 Popular Browsers 
	

 Netscape NAvigator
	    According to the latest statistic floating around the Net, Netscpae Nvigator (most offten referred to simply as Nescape) is used by about 70% of the Web browsing 
            public.  Developed by the same engineers who created Mosaic, Netscape has distanced itself from the  competition  by offering non-standarrd features that make  Netscape.
            
	    
 Microsoft Internet Explorer
	    Thanks to the Microsoft hefty public relations team as well as to the Internet Explorer'r solid performance and the acceptance of all HTML  3.2's tags plus most of 
            the Netscape's is quickly becoming a viable alternative to Netscape, used by some 25% of the Web public.
	
 Basic HTML 
	

 Writing HTML
	     You can create HTML Documents with any word processor or text editor, including the very basic Teach TExt or Simply TExt on the Mac and notepad or Wordpad for Windows,
             both of which come free with the corresponding system software.
             
 HTML Tags
	     HTML tags are commands written between less than(<) and greater than(>) signs, also known as angle brakets, that indicate how the browser should display  the text.  There
             are opening and c;losing versions for many (but not all) tags, and the affected text is contained within two tags.  Both the opening and closing tags use the same command word
             but the closing tags carries an initial extra forward slash symbol.
	    
 Values
	     Attributes in turn often have values.  In some cases, you must pick a value from a small group of choices.  For example, the CLEAR attribute for the BR tag can take value of left,
             right, or all.  Any otehr values give will be ignored.
	    
 Attributes
	     Many tags have special attributes that offer a variety  of options for the contained text.  Teh attribute is entered between  the command word and the  final greater than symbol.  
             Often, you can use a series of attributes in a single tag.  Simply write one after the other with space between each one.
	    
 Quotation Marks
	     Generally speaking, attribues that accept any value require that yoyu enclose the value in straight quotaion marks(").  It is a good idea to use quotes around any URL to ensure that
             it is not misinterpreted by the server.
	    
 Nesting Tags
	     In some cases, you may want to modify your page contents more than one tag.  For example, you may want to add italic formatting to a word inside a header.  There are two things to keep
             in mind here.  First, not all tags can contain all other kinds of tags.  Second, order is everything.  Wheneve you use a closing tag it should correspond to the last unclosed opening tag.
             In other word, first A then B, then B, and then A.
  URLs 
	     Uniform resource locator, or URL, is a fancy name for address.  It contains information about where a file is and what a browser should do with it.  Each file on the internet  has a unique 
	     URL.
	     The first part of the URL is the Protocol.  It tells the browser how to deal with the file that is about to open.  One of the most common protocols you will see is the HTTP, or Hypertext Transfer
	     Protocol.  It is used to access Web pages.
	     The second part of the URL is the name of the server where the file is located, followed by the path that leads  to the  file and the file's  name itself.  Sometimes, a URL  ends in a trailing forward slash
             with no file name given.  In this case the URL refers to the default  file  in the last directory  in the path (which generally corresponds to the homepage.)
	     Other common prtocols  are HTTPS, for secure Web pages, FTP(File Transfer Protocol) for downloading files from the Net, gopher, for researching for information, News, for sending and reading messages posted to 
	     a Usenet news group, and Mail to for sending an electronic Mail.
	     A protocol is generally followed by a colon and two forward slashes.  Mail to  and New are the  major exceptions:  these take only a colon.  Always type protocols in lower letter case.

 MARKUP TAGS 

  HTML 
	     This element tells your browser that the file contains HTML-coded information.  The file extension .html also indicates  this an HTML document and must be used.
  HEAD 
	     The head element identifies the first part of your HTML-coded document that contains the title is shown as part of your browser's window.
  TITLE 
	     The title element contains your document title and identifies its content in a global context.  The title  is also what it is displayed on someone's hotlist or bookmark list, so choose something descriptive, unique, 
	     and relatively  short.  A title is also used during a WAIS search of a server.
  BODY 
	     The second-and-largest-part of your HTML documents is the body, which contains the content of your document, The tags explianed below are used within the body of your HTML documents.
  HEADINGS
	     HTML has six levels of headings, numbered 1 through 6, with 1 being the most prominent.  Headings are displayed in larger and/or border fonts than normal body text.  The first heading in document should be tagged.
  PARAGRAPHS 
	     A browser ignores any indentations or balnk lines in the source text.  The closing tag can be omitted.  This is becuse browsers understands that when they encounter 
  tag, it implies that there is an end to the previous 
	     paragraph.
  FORCED LINE BREAKS/POSTAL ADDRESSES
             The break tag forces a line break with no extra (white) space between lines. Using 
 eelments for short lines of text such as postal addresses result in unwanted additional white space.
	
  LIST 
	     HTML supports unnumbered, numbered lists.  You can nest lists too, but use this feature sparingly because too many nested items can be difficult to follow.

           
Unnumbered List
            To make an unnumberd list, bulleted list start with an opening list 
(for unnumbered list tag, entered the list item  tag followed by the individual item n o closing tag is needed, end the entire list wiht a closing list tag.
 
 Numbered List
     A numbered list (also called an ordered list, from which the tag name  derives) is identical to an unnumberd list, except it uses an Orderd List tag instead of Unnumbered List Tag.  The items are tag using same List tag.  
 
 Definition List
     A definition list usually contains of alternating a definition term and a definition.  Web browsers generally format the definition on a  new line.
 
 Nested List
     List can be nested.  You can  also have a number of paragraphs, each containing a nested list, in a single list item.