Going through the number of times WCAG is mentioned in Twitter and blogs, I find that it has not got the publicity it deserves. Most developers tend to think of accessibility as a luxury they cannot afford. Consequently it finds its place way down in their priority list. However, as we shall see, making a site accessible will not cost you a lot. And accessibility is not only aimed at addressing the needs of disabled, but people who use text browsers, low resolution monitors etc. Thus if your site is designed with accessibility in mind, you will surely see more traffic to your site.

World Wide Web Consortium (W3C) is responsible for developing Web Content Accessibility Guidelines (WCAG) documents. The first version, WCAG 1.0, was published in May 1999. The latest WCAG 2.0 was released on 11^th December 2008. The primary intent to publish these documents was to make web content easily accessible to everyone irrespective of any disabilities. WCAG 2.0 is designed in such a way that it is simpler and easier to understand for the web developer community. The document is built on four foundational principles. Then, there are few guidelines provided under each principle. Each guideline is challenged by different testable success criteria. Satisfaction of all these criteria will make the web site conform to WCAG. Let us go through the four principles in brief.

Perceivable

The first principle implies that any content that is displayed on the website must be perceivable. The dictionary meaning of the word perceivable means ‘To achieve understanding of’, ‘To become aware of directly through any of the senses, especially sight or hearing’. In our context, it means that anyone who accesses the web for content should be able to apprehend the information that is presented.

There are four guidelines furnished to illustrate this principle. The first two coerce to provide text alternatives for non-text content and time-based media. This would enable the user to enlarge or render in whatever tactile form as needed. The third guideline focuses on the structure and presentation of the content. A simple design that complies to the standards will reduce the complexities when there is a requirement to extract content and present to debile users. Sometimes distinguishing foreground information from background can become difficult. The fourth guideline helps avoid this conflict and focuses on making information distinguishable. Success criteria are determined on color, contrast, background audio, text images and many more.

Operable

The second principle deals with the operability of the user interface components. Users can come across situations where they are not able to interact with the content due to issues in links, user controls and other navigation.

The first guideline under this principle recommends making all the functionality of the content available from a keyboard. This does not outweigh the use of mouse and other interfaces. On the contrary, it means that complete dependence on these devices must be forgone. The guideline also cautions of keyboard traps and advices methods to keep the user away from them. The other guidelines focus on ensuring that the users will be able to complete the tasks required by the content with their own individual response times. For every time limit automatically set by the content, it requires the user to have options to turn it off, adjust and also extend the limit. They also caution the design about seizures mainly occurring due to excessive use of Flash. The last guideline recommends helping the users in their navigation to find content. There are 10 success criteria listed to check whether a user is properly guided.

Understandable

Understandability is the next issue the document addresses. The principle mainly targets the people in the lower part of the intellectual group. It compels the developer to make the content easily available in predictable ways and also help the user avoid and correct mistakes.

The first guideline stresses on making the content readable and understandable. Success criteria are set on languages, abbreviations and pronunciations. It also speaks about restricting unusual words or phrases including idioms and jargon. The other guidelines show light on making the pages predictable and providing assistance to the user in mistake-prone sections. Using instructional labels and help pages can assist the user in different areas.  Detecting errors and reporting immediately, as and when the user is inputting information is also a better method of assistance. These together form the success criteria for this principle.

Robust

The last principle is the most important of all the four. It checks the robustness of the content. Accessibility by user agents is checked here. There is only one guideline and it speaks about the compatibility of the content with the current and future technologies. Avoiding deprecated features of W3C technologies makes the site more compatible. Success criteria are designed for custom user interfaces to check compatibility.

Adhere to the guidelines suggested in WCAG 2.0 will bring in more traffic. Therefore it is essential from the developers’ point of view to know these standards and make them a part of our work.

Link for further study:
http://www.w3.org/TR/WCAG20/