Unobtrusive Javascript

Javascript is a wonderful tool to enhance the usability of web sites. It is the extra layer above the mark-up "what is this text" and the CSS "how should it be displayed". Javascript adds a new dimension, the "how should this element behave".

New Article: From DHTML to DOM scripting

Get the Coursebook

This course is now also available in printable format. It features

Rewritten and amended course material
Syntax highlighted code examples
Two extra chapters:
- DOM accidents - explaining accessibility problems to avoid when scripting the DOM
- Outdated JavaScript techniques - why not to use and how to replace them with more modern techniques

You can download a sample chapter (120KB, PDF format) or buy the course as a book or an ebook at lulu.com.

On the following pages we will discuss and see how we can use Javascript, but still maintain accessibility. The technique to completely separate Javascript from the other two layers of web development has become commonly named "unobtrusive Javascript", as "accessible Javascript" does not quite cut it. You can have a perfectly separated Javascript and still be totally inaccessible.

Anyways, let's cut to the chase.