August 2008
By Henny Swan, Senior Web Accessibility Consultant, RNIB
The Web has evolved considerably since 1999 when the Web Content Accessibility Guidelines (WCAG) version 1.0 was published. Today, we see increased functionality, interactivity and use of technologies such as multimedia, Flash, AJAX, and more. Combined these bring a richer experience to most Web users but due to their complexities have left many disabled users behind. The WCAG version builds on WCAG 1.0 to accommodate all of today's Web technologies and help bring an accessible rich experience to all Web users.
WCAG 2.0 has drawn much comments and debate from the Web development community but the time is fast drawing near when many of us, if we haven't already, will need to start implementing WCAG 2.0 in our own or our clients' Web projects. While WCAG 1.0 is, at the time of writing, the current published version of the guidelines, WCAG is expected to be published very soon and there is no time like the present to start working with the new set of guidelines.
Even if you have been working with WCAG 1.0 this can seem a daunting task, however the Web Accessibility Initiative, the people who write the guidelines, have provided some excellent resources to help you understand how to update your Website from WCAG 1.0 to 2.0. So if you are wondering how to start with WCAG 2.0 here are a few resources (all of these documents can be reached from the Overview of WCAG 2.0 at http://www.w3.org/WAI/intro/wcag20.php(External Link)):
This introduces the WCAG 2.0 suite of documents that support the normative WCAG 2.0 document. If you want to understand how all the documents relate to each other this is the place to start.
This is a great tool if you are listing what WCAG 2.0 guidelines and success criteria (formally checkpoints under WCAG 1.0) are relevant to your Website. Using the form on the page you can customise the contents based on whether you are using CSS, multimedia, SMIL, JavaScript or ARIA. You can also only show Level A, AA, or AAA success criteria depending on your chosen level of conformance as well as choose to show or hide techniques and advisory techniques.
This document groups WCAG success criteria one by one. Each page provides information on the purpose of the success criterion, examples, resources, techniques, common failures and key terms. This is great if you want to focus on one topic area, learn whom it affects and proposed solutions.
If you've been working with WCAG 1.0 you will want to know what is new in WCAG 2.0, updated, removed or the same. This document maps the two versions as well as flags the differences.
There are a number of clear benefits for the Website owner, designer and developer using WCAG 2.0 rather than WCAG 1.0.
Testable: The success criteria are written in such a way that they are testable statements unlike WCAG 1.0. For example where WCAG 1.0 Checkpoint 2.2 said "Ensure that foreground and background color combinations provide sufficient contrast...", WCAG 2.0 Success Criteria 1.4.1 says "Text or diagrams, and their background, have a luminosity contrast ratio of at least 5:1.". This makes it much easier to test and less open to interpretation.
Support of Non-W3C Technology: unlike WCAG 1.0, 2.0 is written for all technologies not just W3C technologies. This means WCAG can be used with Flash, PDF, Silverlight and so on.
More Supporting Documentation: the supporting documentation for WCAG contains more examples, explanation of techniques, rationale of how issues affect the users and common failures to avoid.
Updatable Techniques: As new techniques are developed over time by the Web community these can be submitted to WAI for inclusion in the techniques document.
For those who are working on AJAX applications WCAG 2.0 is supported by the WAI Accessible Rich Internet Applications suite (also known as WAI ARIA) which includes a new specification to support the development of accessible AJAX. Combined, WCAG and WAI ARIA, should provide the grounding for an accessible, rich Internet experience for all users.
If you have already been working with WCAG 1.0 you will be on your way to meet WCAG and now is a great time to start. If you have not yet worked with WCAG 1.0, 2.0 is a great place to start as it provides a wealth of explanation, support, examples, tools and resources to build truly exciting and accessible web sites and applications. WCAG is also a much more robust set of guidelines to support web sites in the Web 2.0 world.