HTML (Hypertext Markup Language) stands out to be the main stakeholder in building a website or web application. It has a flexible syntax to apply formatting on hypertext and make the content presentable.

An XHTML (eXtensible Hypertext Markup Language) document integrates HTML(tags/elements) and XML(rules). Although it is like HTML but has stricter syntax. This article provides an abstract intro to HTML and XHTML along with a head-to-head comparison of both markup languages.


HTML is the key contender in developing web pages. A web page may comprise various sections, headings, images, forms, navigation, and many more. HTML provides extensive support for elements, attributes, and values. All these instances are put together to develop a web page. For better understanding, we have provided a sample of an HTML document shown below.

The HTML document comprises of the following instances,

  • a DOCTYPE is defined that is HTML (the DOCTYPE is optional in HTML)
  • the <html> tag is exercised to define the main content of the document
  • the <head> tag contains the character set (UTF-8) and viewport of the browser(where the content will be displayed)
  • after the head tag, the main is started

Let’s explore some notable advantages and disadvantages of HTML.


  • It is suitable for beginners as it does not put any restrictions on formatting.
  • The support is available around the globe as it is a widely used markup language.
  • Supported by widely used browsers
  • Its integration with backend frameworks is quite easy, such as PHP, Node.js.


  • It develops static web pages.
  • The errors may be difficult to resolve in the case of complex code.
  • A lengthy HTML code would be complex to reuse.


XHTML is an extension of HTML which integrates XML with HTML to develop web applications. As XHTML is an advanced version of HTML, it produces web pages that are more good-looking as compared to HTML. Like other markup languages, SGML (Standard Generalized Markup Language) is the basis for XHMTL as well.

Initially, the attributes and tags supported by HTML4 were used as building blocks of XHTML. These tags/attributes were then assisted by XML rules to define their working. Thus, XHTML has been developed to incorporate the potencies of XML and HTML.

A sample XHTML document is shown in the following image

The instances of an XHTML document are

  • character set(UTF-8)is defined in the first line
  • the DTD (Document Type Definition) is defined and is set to strict (it can be transitional or frames).
  • the XML namespace is declared in the <html>

Note: The strict DTD is used when you are using tags from state-of-the-art. The transitional is used when the standard of XHTML is not being followed properly. The frames DTD is practiced when you are using frames in your XHTML.

The noteworthy strengths and limitations of XHTML are provided below.


  • The XHTML follows strict formatting rules that make the code aesthetically perfect and reusable as well.
  • The XHTML code is adaptable and can be converted to various file formats such as PDF and RFT.
  • Using XHTML code, you can reduce site loading time
  • The XHTML reduces the cost as it requires smaller bandwidth
  • It can integrate HTML with XML applications

Note: RFT files are used to create Revit projects (integrates 3D objects).


  • The strict formatting rules make it unsuitable for a new developer
  • Limited support for browsers of the current era

Head-to-Head: HTML vs XHTML

Although HTML and XHTML look alike, they do have differences in their operations. Let’s dig into these differences one by one.

Case sensitivity: HTML is not a case-sensitive markup language whereas XHTML follows case-sensitivity rules that make XHTML more specific (every user has to write the letters in lower case).

DOCTYPE: The DOCTYPE in HTML is not necessary to write but XHTML must start with the DOCTYPE.

Tag closing: The tags in HTML can be ended in any order whereas the order of closing tags must be followed in XHTML.

Attributes: The attributes in HTML can be added without quotation marks whereas XHTML does not accept the attributes without quotation marks.

This comparison should have helped you come to a basic understanding of HTML and XHTML.


HTML and XHTML both aim to develop web pages. XHTML is a more advanced and strict language than HTML. This post demonstrates the comparison of HTML and XHMTL. The HTML is easier to use and therefore recommended for novel web developers. Contrary to this, the strict formatting rules of XHTML make it suitable for intermediate or experienced developers.

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Adnan Shabbir