"The power of the Web is in its universality. Access by everyone regardless of disability is an essential aspect."
Tim Berners-Lee, W3C Director and inventor of the World Wide Web
Web accessibility refers to designing websites and web technologies in such a way that people, especially those with disabilities, can easily access the web and its content. This provides equal access and equal opportunity to people no matter their age, language, physical and mental abilities, and the hardware and software they utilize. By adopting web accessibility techniques, we provide a more user-friendly web that connects more people to more content.
There are four categories of disabilities that affect the way users work with the web. These include:
Web accessibility seeks to create alternative ways for people with the above disabilities to access content. Although web accessibility is intended for people with disabilities, the strategies can also benefit others, such as older people and those with low-quality browsing experiences.
The concept of accessibility applies to multiple components. On the developer end, this includes authoring and evaluation tools in addition to different design strategies to produce accessible content. Users access this content through browsers and media players, and with the use of assistive technologies. All components, though, need to adopt accessible ideas in order to be successful.
There are two great places to start to better understand accessibility. The first is Accessibility and has a great introduction. The second is the Web Accessibility Initiative (WAI) from the W3C. The WAI brings together people, design strategies, and resources to help guide web developers with accessibility, especially with their guidelines.
The Web Content Accessibility Guidelines 2.0 (WCAG 2.0) are the accepted standards for web accessibility. Designed by a diverse group of experts from various professions, the WCAG 2.0 contains 12 guidelines organized by four principles – perceivable, operable, understandable, and robust. Each guideline has testable success criteria in three levels (A, AA, and AAA) which guarantee the content is web accessible if adopted.
In addition to the guidelines, a checklist is also available that is intended to make it easier for web developers to follow the guidelines. The checklist, which is customizable, can be accessed here: http://www.w3.org/WAI/WCAG20/quickref/.
There are many tools available to help make websites more accessible. Below is a selection that can help when designing a site. In addition to the WCAG 2.0 Guidelines above, see Designing for Inclusion from the WAI to see how people with disabilities use the web and how accessibility applies to others like older people.
Picking color for a website seems relatively simple – just pick the color that looks the best. Unfortunately, not all people see color the same since some are color blind. People who are color blind might have difficulty seeing the content of a website if the site is not accessible to them. There are several tools available to help pick colors and recreate what sites would look like if you were color blind. For a basic understanding of color blindness, see Visual Disabilities: Color-blindness from WebAIM.
The Colorblind Web Page Filter allows users to enter a URL of a site and apply a color filter to see what the site would look like to people who are color blind.
The Accessible Color Wheel helps users select background and foreground colors that will be visible to all people, including those with vision problems. A large green check or red ‘x’ quickly informs users if the colors work or not, and the site provides colors in hexadecimal values to easily apply them to a website's code.
After a website is developed – or while it is in the process of being developed – a developer has access to multiple tools to evaluate whether or not their site is accessible. Here are some of them:
The first place to start is Easy Checks – A First Review of Web Accessibility. This site lists the most basic ways to make your site accessible. If a developer adopts the design strategies as they design their site, then you'll ensure that you are accessible.
Another evaluation tool is the WAVE: Web Accessibility Evaluation Tool. The WAVE lets a user input a URL and run a check of the site. It looks at document structure, contrast, and interactive features to help you see errors and fix them.
While this is not a tool per se, the governments Section 508 site has specific information on Web-based intranet and internet information and applications. These are similar to the WCAG 2.0 Guidelines but are the law; in fact, eleven of the sixteen paragraphs are consistent with WCAG 1.0 Guidelines, the guidelines that existed prior to the 2.0 guidelines. Also, the customizable checklist of the WCAG 2.0 Guidelines is also which provides even more detail.[Back to top]