In May 1999 the Web Accessibility Initiative (WAI) published Web Content Accessibility Guidelines 1.0 (WCAG 1.0) and since then they have been the benchmark for testing the accessibility of web sites. Since that time, web technology, and the understanding of accessibility, has progressed significantly. Soon after WCAG 1.0 was published work began on WCAG 2.0 and the first working draft was available in January 2001. It has taken a great deal of time and effort to get to the Proposed Recommendation which was published 3rd November 2008 and it is expected that the final publication will be before the end of the year.
It is recommended that website commissioners and developers start to implement the new guidelines immediately. The new guidelines will improve the access to websites for everyone but particularly people with disabilities.
The differences between 1.0 and 2.0 can be divided into two major areas. Firstly, changes to the details of the guidelines which include correction of errors, additions for new technology and current best practice based on experience since 2001. The second area is changes to make the guidelines themselves more accessible and understandable.
I believe that the second area is vital to the future success and acceptance of accessibility so I am going to use the rest of this article to introduce the guidelines in such a way that anyone who is involved with web site commissioning or development should be able to understand.
The guidelines first describe four attributes that a web site must have for it to be accessible:
- Perceivable - Information and user interface components must be perceivable by users. Perception can either be visually or through the intermediary of an assistive technology (AT).
- Operable - User interface components must be operable by users. In particular it must be usable by people who cannot use a mouse.
- Understandable - Information and operation of user interface must be understandable by users.
- Robust - Content must be robust enough that it can be interpreted reliably by a wide variety of user agents, including assistive technologies.
The acronym POUR makes the attributes easy to remember.
The guidelines then define checkpoints that, if followed, will ensure the websites has the POUR attributes. There are just the following 12 checkpoints:
- 1.1 Text Alternatives: Provide text alternatives for any non-text content so that it can be changed into other forms people need, such as large print, braille, speech, symbols or simpler language.
- 1.2 Time-based Media: Provide alternatives for time-based media.
- 1.3 Adaptable: Create content that can be presented in different ways (for example simpler layout) without losing information or structure.
- 1.4 Distinguishable: Make it easier for users to see and hear content including separating foreground from background.
- 2.1 Keyboard Accessible: Make all functionality available from a keyboard.
- 2.2 Enough Time: Provide users enough time to read and use content.
- 2.3 Seizures: Do not design content in a way that is known to cause seizures.
- 2.4 Navigable: Provide ways to help users navigate, find content and determine where they are.
- 3.1 Readable: Make text content readable and understandable.
- 3.2 Predictable: Make Web pages appear and operate in predictable ways
- 3.3 Input Assistance: Help users avoid and correct mistakes.
- 4.1 Compatible: Maximize compatibility with current and future user agents, including assistive technologies.
The strange numbering is to relate the checkpoints to the related attribute, so for example checkpoint '3.1 Readable' relates to the attribute '3 Understandable'.
The rest you may say is just commentary, explanations, examples and techniques; obviously essential but nonetheless just detail.
The best place to start investigating the guidelines further is the WCAG FAQ pag.