This is a community wiki. Be sure you are logged in to edit, comment, and add pages. Not a member yet? It's free and simple. Click Login in the upper right corner and Register.
View a PDF of the original wiki content produced in March 2008 by Lotus and IBM Redbooks.

Dynamic HTML (DHTML) is the combined use of HTML, CSS, and JavaScript to create dynamic Web pages.

DHTML involves the manipulation of the HTML Document Object Model (DOM). Consequently, it's rather important your HTML document is well formed:

• Close all container tags such as <p>, <div>, and <li>.
• Always use a DOCTYPE definition.
• Use semantic rather than presentational HTML, i.e., use tags that describe meaning rather than presentation such as <strong> rather than <b>.
• Validate your HTML (the W3C has an often used validator at http://validator.w3.org).

In addition to valid HTML, ensure that you are using CSS for the presentation of your Web pages and you're using external style sheets. HTML gives Web pages structure, CSS should be used to define how they look.

The Dynamic portion of Dynamic HTML is supplied by JavaScript. If you're not familiar with JavaScript, see the JavaScript primer in this wiki. You want the ability to debug your JavaScript on the off chance there is a bug in it. If you're using Firefox, you can launch a JavaScript Console for debugging simply by typing javascript: in the address bar:

As you can see from the previous example, the JavaScript Console also informs you about errors in your CSS.