This chapter demonstrates about the XHTML Tutorial XHTML is the formulation of the HTML 4.01 in XML and combination of strength of HTML 4 and XML, following are the concepts are covered in this chapter.

• History of XHTML
• Basic Understanding
• Advantages and Disadvantages

XHTML is known as the Extensible Hyper Text Markup Language which is the part of the XML markup languages and the extension version of the Hyper Text Markup Language(HTML). XHTML 1.0 became a World Wide Consortium (W3c) recommendation on 26th January 2000. XHTML 1.1 became a W3c Recommendation on 31st May 2001. The Standard version of XHTML5 developed on XML adaption of the HTML5 specification. In the year of 2005 Web Hyper Text Application Technology Working Group (WHATWG) independently of the W3c. HTML5 is parallel to the W3c Standards such as XHTML2 which are developed in the year of 2007. XHTML is similar to the HTML 4.01 with slight changes if user already familiar with the HTML 4.01 user need to have some attention to learn the latest version of XHTML.

In order to learn completely about XHTML user need to have the some basic knowledge about the HTML, XML, SGML. HTML HTML is Standard Generalized Markup Language (SGML) which is standard publishing language of the World Wide Web and SGML conforming to International Standard ISO 8879. XML XML is known as EXtensible Markup Language which same as HTML, and is developed to derive the data. XML doesn't have predefined tags user need to define his own tags based on his requirement. SGML SGML is a language which describe the markup languages, particularly which are used in document publishing, exchanging, management. The best example for the SGML is HTML.

There are many advantages and disadvantages some are listed below. Advantages

• Extensibility All XHTML tags are extensible and user can also add on our own tags.

• Portability Created new tags are understood by all the users.

Disadvantages

• XHTML is not that much easy like HTML because XHTMl have some ridge rules.
• XHTML DTD Will contains HTML only and user should need do the HTML Declaration present at the top of the document.
• XHTML and HTML go against the go against the rules of W3C.

• XHTML is similar to HTML 4.0.
• XHTML 1.0 is the initial document in the XHTML family.
• XHTML developed by W3c World Wide Consortium.