Chapter 7. Accessibility

Anitra Pavka


“Disability” is a broad term. Major categories of disabilities that affect use of the Web include visual, hearing, cognitive, speech (especially on mobile devices), and motor disabilities. A single category of disability may manifest in many forms. For example, visual disability includes, but is not limited to, red-green color blindness.


About 7 to 10% of all men have trouble differentiating between red and green colors.

People may have varying degrees of disability and even multiple disabilities. Like a broken wrist or an amputation, disabilities can be temporary or permanent. And permanent disabilities may be present from birth or start later in life.

In short, anyone can become disabled.

The Purpose of Accessibility

Web accessibility is about removing barriers that prevent people from using the Web. In fact, one could say accessibility is at the heart of the Web in that its goal is to break down barriers of communication.

According to the World Wide Web Consortium (see

The Web is fundamentally designed to work for all people, whatever their hardware, software, language, culture, location, or physical or mental ability. When the Web meets this goal, it is accessible to people with a diverse range of hearing, movement, sight, and cognitive ability.

Web coding and markup is a critical part of removing barriers. But done incorrectly, it can erect more barriers.

The hardware and software ...

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