HTML is a mark-up language, while DHTML is a collection of technology.
DHTML creates dynamic web pages, whereas HTML creates static web pages.
DHTML allows including small animations and dynamic menus in Web pages.
DHML used events, methods, properties to insulate dynamism in HTML Pages.
DHML is basically using JavaScript and style sheets in an HTML page.
HTML sites will be slow upon client-side technologies, while DHTML sites will be fast enough upon client-side technologies.
HTML creates a plain page without any styles and Scripts called as HTML. Whereas, DHTML creates a page with HTML, CSS, DOM and Scripts called as DHTML.
HTML cannot have any server side code but DHTML may contain server side code.

All above comments makes easy for me to understand difference between HTML and XML.
Thanks

Main Difference between HTML and XML
 

HTML abbreviates for HyperText Markup Language while XML abbreviates for Extensible Markup Language. There are many differences between HTML and XML but the main difference is that HTML was designed to display data with the focus on how the data looks and XML was designed to store data with the focus on what the data is.

HTML is an abbreviation for HyperText Markup Language. HTML was designed to display data with focus on how data looks. XML was designed to be a software and hardware independent tool used to transport and store data, with focus on what data is. XML provides a framework for defining markup languages

HTML is a basic website development language xml is a layout langauge for websites, Using the xml you can add the new layout for your site

The prior difference is that in XML there are provisions for defining new elements while HTML doesn't provide a specification to define new element and it uses predefined tags. XML can be used to build markup languages while HTML itself is a markup language