Lesson 2: How People with Disabilities Access the Web
One of the groups of users who benefits most from standard-based web design is people with disabilities. Consider the following examples:
- If a web page includes visual content (graphic images), a person who is blind can't see it. These individuals might access the computer's output using synthesized text-to-speech technology known as a "screen reader", or they might use a small Braille output device. Images must be accompanied (in the code behind-the-scenes) with alternate text that describes the content of the images for anyone who is unable to see visual content.
- If a web page includes audio content, a person who is deaf or hard of hearing won't be able to hear it. This content must also be provided as text, such as in a transcript. If the site includes video, that file should be closed captioned. Closed captions appear in a text track, usually at the bottom of the video player, so users who can't hear the audio (or who don't speak the language) can tell what's being said.
- If a web page has buttons, controls, menus, form fields, etc., that require a user to click on them with a mouse, users with physical disabilities who are unable to operate a mouse will be unable to access these controls. All controls should be operable with a keyboard as well.
At the completion of this exercise:
- you will have developed a basic understanding of the variety of methods and technologies used by people with disabilities in accessing computers and the web.
- you will have experienced some of the common barriers people with disabilities face with inaccessible web content.
- Videos: View and discuss each of the Web Accessibility Perspectives videos available on the W3C website. These videos provide examples of how people with disabilities access computers and other technologies, and the problems they may encounter when trying to access web content.
- Simulation: Visit and evaluate several websites and discuss whether some users might have difficulty accessing these sites. Ask your instructor for the URLs of websites that make particularly good examples of either accessible or inaccessible design. Explore ways of determining whether sites are inaccessible. Here are some examples:
- Turn off images in your browser to perceive each page as a blind user might encounter it.
- If you have access to a screen reader application, turn off the monitor and try accessing websites audibly (some operating systems come equipped with free screen readers, such as Microsoft Narrator in Windows or VoiceOver in Mac OS X). There are also free screen readers available, such as NVDA.
- Try accessing a page without using your mouse (if you can't resist, disconnect your mouse!)
- Try watching a video with the sound muted.
- More videos, from DO-IT (University of Washington)
- WebAIM: articles and tutorials on all aspects of accessible web design
Great! Proceed to Module 4.