The Main Difference Between XML and HTML:

The single biggest weakness of HTML is its lack of extensibility, for instance in order to display a mathematical formula one had to use a different tool that produces a GIF image. Not only is this inconvenient, but all information about the formula, including the fact that it is a formula, are lost through this forced conversion.

This is where XML with its extensibility comes in. XML was used to define a standard for mathematical formulas called MathML, and many others for various subject areas. Some of those will be directly supported by browsers, others might be converted on the fly to a lower-level representation rather than manually converted. There is an XML formulation of HTML called XHTML.

• XML was designed to carry data.

• XML is not a replacement for HTML.

XML and HTML were designed with different goals:

• XML was designed to describe data and to focus on what data is.

• HTML was designed to display data and to focus on how data looks.

• HTML is about displaying information, while XML is about describing information