What is DHTML?
     DHTML, or Dynamic HTML, is not a language in and of itself like HTML or JavaScript. Rather, it's a method used to design a web page by mixing HTML, CSS and scripting all into one, working document. If we had to call it anything, it probably would be called a hybrid language since it uses the highlights of HTML, CSS and scripting. Ultimately, it gives the designer complete control over the web page positioning, look and behavior.

What is Needed?
     First, you need knowledge of HTML, CSS (cascading style sheets) and some scripting language such as JavaScript or VBScript. Second, you need either Internet Explorer 4 (or higher), Netscape Navigator 4 (or higher) or both. The reason for this is that these are the only two browsers that provide support for DHTML. It would be best to have both, though, because they have different ways of using DHTML. Lastly, you would need a text editor to write and edit all the code. If you use a WYSIWYG, (What You See Is What You Get), editor, now is a good time to learn how to use a text editor, unless it has special support for writing DHTML.

What it Can Do
     DHTML gives you ability to position elements of a web page to precise (x,y,z) coordinates and dynamically change the position with script. Every property of a web page element can be altered with the use of a script language. Some properties include color, size, visibility, alignment, etc.. You can achieve some awesome effects with DHTML.

How Does it Work?
     Various elements of a web page such as images and blocks of text are organized into groups with the <div> or <layer> tags. The groups are then given a list of properties using the cascading style sheet specification and a name to distinguish them from each other. Then through the use of a scripting language, you can dynamically change the CSS attribute of each group. It's really quite neat how the three elements of web design can come together in a dynamic union.

Should I Learn DHTML?
     Right now, DHTML is only readable with Internet Explorer and Netscape Navigator so it's not really priority one knowledge. It's good for fun and added effects on your pages but due to it's limited support and unstanderdization between browsers, probably shouldn't be used for major sites. If you do choose to do your web pages in DHTML be sure to allow the users without a compatible browser the choice to view a non-DHTML version of your site.

Related Article: Basic DHTML with Internet Explorer
Related Article: Basic DHTML with Netscape Navigator

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