Web Technologies
Anupriya Sharma
Table of Content
HTML
XHTML
XML
HTML
What is HTML
History
What is it used for
Tags & Structure Sample
Conclusion
What is HTML
HTML (HyperText Markup Language)
Language for publications in the World
Wide Web, text format for HTTP
Basic language = English
Developed 1990 by Berners Lee;
based very strongly on SGML
SGML: a Brief Introduction
Standardized General Markup
Language
In 1986, ISO approved an international
standard for descriptive markup
SGML is a metalanguage for defining
markup languages
HTML is one example of an SGML-
defined language
History of HTML
HTML 2.0 is the official standard, which defines
those basic functions of HTML, which are
meaningfully represented by all Web Browsern.
HTML 3.2 is the most common used standard,
which covers those HTML elements, which are
supported to a large extent by nearly all Browser
versions (starting from 1996/97).
HTML 4.0 is a suggestion of the W3-Consortium,
which is at least partly supported by newer
Browser versions (starting from 1997/98).
The advancement of HTML starting from
1999/2000 will go into the direction from XHTML.
What is it used for
Presenting information in LAN / WAN
Structure your text-based information
Hyperlinks to reach following texts
To Put images on your docs
Basic structure for all web applications,
like Guestbooks, Online Stores,
Forums, etc
HTML Standard Tags
TAG: A command inserted in a document that
specifies how the document, or a portion of the
document, should be formatted. Tags are used by
all format specifications that store documents as
text files. This includes SGML and HTML.
Attribute refers to the properties of the HTML
elements
TAG is, which stands within "<...>"
to an opening TAG belongs usually a closing TAG
(< font>... </font>)
Comment tags: <!-- .... -->
There are special tags who not need an end tag,
like <br>
HTML Basic Structure
<!DOCTYPE HTML PUBLIC
"-//W3C//DTD HTML 4.01 Transitional//EN"
"http://www.w3.org/TR/html4/loose.dtd">
<html>
<head>
<title>Title of the page</title>
</head>
<body>
<h1><i>HTML</i> - the language of the web</h1>
</body>
</html>
Conclusion
Advantage: HTML is easy to learn
Problems:
Almost nobody really cares about the
standards of w3c, because the Microsoft
Internet Explorer (Leading Browser) is
very obliging
As a result the parsers of the non-microsoft
browsers can have significant problems in
displaying pages correctly
XHTML
What is XHTML
History
Main characteristics of XHTML
Syntax rules
Conclusion
What is XHTML
EXtensible HyperText Markup Language
Supposed to replace HTML
nearly identically to HTML 4.01
stricter and "more cleanly" version of HTML
HTML 4.01 on XML-Base
History
Introduced in 26 January 2000 by W3C
as the new official standard
Reason: Problems because of "bad"
and "unsuitable" HTML => for search
"more cleanly" and "more uniformly"
programming
Main characteristics of XHTML
correct nesting of the tags
XHTML documents must keep a certain
form
permit no capital letters for the tags
All elements must be closed: END tag
necessarily
Important syntax rules
Attribute names must be written in
small letters
Attributes must stand in " "
No attributes shortening
The ID attribute replaces the name
attribute
The XHTML DTD defines obligatory
elements.
Conclusion
XHTML is supposed to make the HTML-
Jungle clean, to make the Web-Pages
suitable for all browser types.
Disadvantages:
Web developers have to obey the rules
Errors will not be tolerated
=> More expenditure of time
XML
What is XML
XML Motivation
XML Classification
Sample
Conclution
What is XML
XML (EXtensible Markup Language)
Guidance for writing of Document Type
Definitions DTDs
XML is more general and uniform than
HTML, and simpler than SGML
SGML - (arcane features) + (new
acronym) = XML!
XML - Motivation
For closing gaps between machine-
machine communication ...
... applicable in the WWW
Easy to create
For humans and machines readable
To cover as much as possible areas of
application
XML - Classification
Semi Non
Structured Data
Structured Data Structured Data
RATIONAL
DATA BASES
XML FLOW TEXT
Sample Code
<?xml version=1.0 encoding=ISO-8859-1 ?>
<book isbn=3423085169>
<titel>Sofies Welt</titel>
<autor>
<name>Gaarder</name>
<firstname>Jostein</firstname>
</autor>
<publisher>DTV</ publisher>
<year>1993</year>
</book>
End - Conclusion
HTML
Markup language for the Web
Version and compatibility problems
XHTML
Tryes to solve this problems
XML
machine-machine communication
Thanks for your attention!
Questions?
