What HTML isn't?

(1) HTML: What It Isn't?
 With all its multimedia-enabling features and the hot technologies that give life to HTML documents over the Internet, it is important also to understand the language's limitations: HTML is not a word processing tool, a desktop publishing solution, or even a programming language, for that matter. That's because its fundamental purpose is to define the structure and appearance of documents and document families so that they might be delivered quickly and easily to a user over a network for rendering on a variety of display devices.
"Jack of all trades, but master of none"- so to speak.
(2) Don't waste your time trying to force HTML to do things it was never designed to do. Instead, use HTML in the manner it was designed for: indicating the structure of a document so that the browser can then render its content appropriately.
To be professional web-designer or web-developer you need learn and use several other web building resources like:
- WYSIWYG web designing software like Dreamweaver, MS-Frontpage
- Instead of WYSIWYG you may use extra features (enhanced) text-editors like Notepad++
- These days more efficient web-development tools are available that can replace above mentioned tools i.e. CMS (Content Management System) like Joomla, Durpal, etc.
Besides GUI/Editors/CMS web-development requires more knowledge on topics like
- XML (eXtended Markup Language)
- CSS (Cascade Style Sheet)
- Server-side Scripting like ASP (Active Server Page) or JavaServerlet or PHP (Hypertext Pre-processor)
 or CGI scriptings like Perl
- Client-side Scripting like JavaScript, VBScript
Besides these you may like make your page or site more graphically rich than you require more extensions of knowledge like
- Graphics softwares like Photoshop
- Animation and multimedia interactive softwares like Flash
- Java applets and other shockwave programs
and many more...