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DEMOS Project

Online Materials for Staff Disability Awareness
: Techniques


In 2001 standard compliant browsers finally arrived and brought with them a new buzzword for the web development community: forward compatibility.

'Backward compatibility' was always part of the definition of accessibility. It refers to ensuring that a website is accessible in older browsers. 'Cross-browser compatibility', on the other hand, refers to the tedious effort of making sites work across a range of browsers using proprietory mark-up and different ways of interpreting instructions.

The World Wide Web Consortium (W3C) [External link: Open in new browser window] has been making recommendations for interoperability since 1994, which now have become recognized as standards by web developers and finally by makers of user agents, too. The latest browsers (Internet Explorer 5+, Netscape 6+, Opera 5+, Mozilla) have been written to comply with these recommendations, which means that web developers can now code according to standards.


Standards are good for accessibility because Universal Access is part of the W3C's mission. Websites written according to standards will be accessible in a whole range of devices: computers, small mobile devices, WebTV, assistive technologies such as screen readers etc.

In addition to that, there are also specific recommendations for accessible web design. The Web Accessibility Initiative (WAI) has created guidelines, checklists and techniques to improve accessibility to users with disabilities and has defined three levels of accessible design techniques (priorities). Links to these can be found on the resources page.

Backward compatibility

Unfortunately some of these new techniques cause problems in older browsers, as in the case of CSS Positioning, a method of positioning elements like navigation bars, main content, header and footer on a page without the use of tables. This method ensures that pages degrade gracefully in user agents that require a simpler layout, but it causes display problems in some browsers that are still in widespread use (e.g. Netscape 4 browsers). For this reason tables will still be used for layout for a while, until non-standard compliant browsers eventually die out.

Forward compatibility

Some techniques, however, don't break old browsers. They are simply ignored, as in the case of the <acronym> tag. Many of these techniques provide improved accessibility for users of assistive technology. Web developers should start using them to make sure their sites are ready for the future and for those who can already benefit from them, users of up-to-date software.


Hover your mouse pointer over the following acronym. If you are using a standard compliant browser a tooltip will pop up.

How this is achieved:

<acronym title="Web Accessibility Initiative">WAI</acronym >

Apart from the obvious advantage of providing users with a way of checking the meaning of an acronym, this technique especially helps users of screen readers (again, just the latest versions).

The title attribute, which is displayed correctly in standard compliant browsers, can be used in a number of tags to provide any kind of additional information, especially for links that are not very descriptive.

There are many more reasons for designing standard compliant sites, some of which are longevity of code, easier maintenance and shorter development time.

The code

Writing standard-compliant code means using the latest W3C recommendations, HTML 4.01 or XHTML 1.0 for structural mark-up and CSS for presentational styles and layout.

Learn more:

To learn more about some of the elements of standard-compliant code have a closer look at the following chapters of this guide:

This article explains the whole issue very well:
A List Apart: Convincing Your Clients to go with Standards [External link: Open in new browser window]

A List Apart: Fixing your site with the right DOCTYPE [External link: Open in new browser window]

See W3C Technical Reports and Publications for a list of recently published recommendations. [External link: Open in new browser window]

More links can be found on the resources page.

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