Definition of the concept of accessibility
According to Tim Berners-Lee, director of W3C and inventor of the World Wide Web, accessibility means to "ensure that the web is available and accessible to everyone, regardless of their hardware, software, network infrastructure, language, culture, location, or physical or mental ability".
W3C, through WAI, has developed the recommendations WCAG 1.0. which suggest practical solutions to achieve the target level of accessibility. WCAG 1.0. consists of 14 guidelines:
- Provide equivalent alternatives to auditory and visual content,
- Don't rely on colour alone,
- Use mark-up and style sheets and do so properly,
- Clarify natural language usage,
- Create tables that transform gracefully,
- Ensure that pages featuring new technologies transform gracefully,
- Ensure user control of time-sensitive content changes,
- Ensure direct accessibility of embedded user interfaces,
- Design for device-independence,
- Use interim solutions,
- Use W3C technologies and guidelines,
- Provide context and orientation information,
- Provide clear navigation mechanisms,
- Ensure that documents are clear and simple.
These 14 guidelines are broken down into 65 checkpoints on 3 levels of priority :
- Priority 1, A: the site must satisfy this checkpoint to allow a minimum access.
- Priority 2, "Double-A": if the site does not satisfy this priority level, people with a disability will have difficulties to access certain of its parts.
- Priority 3, "Triple-A": if the site satisfies this priority level, access will be facilitated. However, this level is not fundamental.
The site is developed according to Transitional XHTML 1.0 technology and CSS2.