How the rules help disabled people

Following the twelve simple rules, you make pages more accessible to many people. This includes the following:

1. Simple language helps people with cognitive disabilities or with dyslexia (difficulty of reading). It is also very important to people who do not know the language of the page well, e.g. because they are immigrants who are just learning it.
2. Descriptive link texts also help people with cognitive disabilities. For example, difficulties in short-time memory make it essential that links are easy to understand and to distinguish from each other. Moreover, people with visual disabilities often use speech browsers in “link reading” mode to get an idea of what links there are.
3. Alt texts are essential to all non-visual browsing (speech browsers and Braille browsers). They may also help people who can see images but have problems in understanding their meaning.
4. Explaining content images, too, is crucial to people with visual disabilities.
5. Avoiding auto-start helps people who easily get disoriented by moving content. Moreover, it helps to avoid conflicts with special software that disabled people may use. If you are using a speech synthesizer for browsing, you do not want any background music to start automatically.
6. Text transcriptions of audio clips help people who cannot hear well enough or have difficulties in understanding the language as spoken. Text descriptions of video clips can be used to generate a speech presentation to people who cannot see well enough. They also help people who have difficulties in understanding speech, gestures, etc.
7. Alternatives to forms help people who find it difficult to fill out forms e.g. due to motoric disabilities or lack of understanding of how forms work. For example, many people have great difficulties in presenting their question or feedback in writing but could easily present it by phone.
8. Avoiding “PDF only” or “Word only” formats mean that the accessibility problems in these formats are avoided. Despite progress in improving their accessibility and despite software vendors’ claims, this is still a very important issue. When a user follows a link to a PDF file, there will usually be a delay, a possibility of software crash, disturbing messages about data format mismatch, etc., and the user interface of a PDF viewer (such as Acrobat Reader) is different from that of a browser. These are often just an inconvenience, but to people with disabilities, they may create serious barriers.
9. Linearizability is essential in non-visual presentation. Visual presentation may also need to be linearized, e.g. in text-only browsers and graphic browsers working on a very small screen.
10. A sufficiently large font size and the possibility of changing the font size easily are essential to people with reduced eyesight. People with considerable visual impairment are not affected, since they use non-visual browsing or a visual browser that uses a sufficiently large font size, irrespectively of settings on the page. But people with less serious problems will keep trying to read texts despite the difficulties. Thus, this problem is relevant to a very large group people. When a page sets font size to very small, e.g. to 9 pixels, the problem may affect the majority of users.
11. Reasonable and adjustable width helps people with some eyesight problems (narrow scope of vision) and people using special devices to access web pages. It also makes it easier (often much easier) to get a good-quality printed copy of the page, and to many people, printed documents are easier to read than on-screen reading. Moreover, many people have cognitive problems when they have to work with a “wide scope.” They can physically see a wide area but they mentally get lost in the wilderness when trying to understand its structure and content.
12. Explaining the inaccessibilities helps people to avoid frustration. When people know about the problems, they can try to find methods of overcoming the limitations (e.g., using a different browser or asking for someone’s help). They can also make rational choices between sites, e.g. between an accessible site and a more content-rich but less accessible site about the same topic. Besides, if you can make and keep promises about fixing the problems, the offence will be reduced and people will know that they can return to the site later.