Accessible Web Page Design

This is writing Web pages so as to ensure correct interpretation in as many browsers as possible.

There is much written about this on the net.

The techniques include:

avoid depending on size of browser window, browser's ability to display graphics and other non-textual data, browser's support for scripting, and so on
use standard HTML
avoid ambiguous HTML
avoid or supply alternatives to HTML that are not included in earlier standards
use an HTML validator such as http://validator.w3.org
simply refrain from attempting to "control" the user experience

What is meant by "ambiguous HTML"? Does this refer to proprietary extensions to the HTML specifications?

MarkPilgrim's Dive into Accessibility tutorial is a must.

I normally understand AccessibleWebPageDesign to mean Web content accessible to people with disabilities, a la http://diveintoaccessibility.org/.

I totally appreciate the need to make webpage accessible by people of all abilities, but I think there're more issues to consider when looking at computers with disabilities (aawwww, poor things) like those without the ability to use Flash or Shockwave or those with early browsers or non-standard browsers or no speakers, bad graphics and sound cards etc. -- sw

This is applying an 'everyday' definition of accessibility, as opposed to accessibility in the context of web design. The second includes the first. I like the definition at http://www.anybrowser.org/campaign/abdesign.html#accessibility. For an overview on accessible webpage design from the eyes or a new disabled web-designer, http://www.tunna-resources.co.uk gives you all the info a beginner could need.

In addition to "accessibility," "usability" is a related, often overlapping, issue in the design of individual web pages and the overall organization of the site. A web page is a UserInterface and needs thoughtful design.

"Alertbox: Current Issues in Web Usability," a bi-weekly column by JakobNielsen, makes interesting reading: http://www.useit.com/alertbox/.

Or for examples of hilariously inaccessible, unnavigable, and generally incomprehensible sites, enjoy your visit to the WebPagesThatSuck site. For example, http://www.chipotle.com/ (FlashAlert), the trendy restaurant chain, is atrocious. The site is trendy, all right, but what's with the "mystery meat navigation"?