Thursday, November 29, 2007

Accessability (working with blind readers)

The main "new technologies" for improved accessibilities are the browser extensions such as blind readers. These work best when content is built in HTML because it is presented as text. When courseware is built in Flash or Java, while it has nice animation capabilities, it is NOT accessible to blind readers.

Many developers have added audio to their courses in order to satisfy the accessibility for visually impaired users. However, this can actually be a disservice. Blind users usually set their blind readers to speak at about 3 times the normal rate since they have to receive all data in a serial manner. If they have to depend on a narrator (often non-professional), the content is fed to them way too slowly. If, however, the content is built using HTML and following best practices (see a blind reader can then read this at whatever rate the user has established.

Following good web design practices has additional benefits for users without disabilities:
1. Content can be searched using a search engine, so that users can get to the content of interest more quickly.
2. The content can be delivered to different size screens (you don't have to established a fixed window size)
3. The content can be delivered to other devices such as PDAs and cell phones
4. The end-user can set their own preferred font size/color (through their browser configuration), and they are not forced to read the designer's preferred 8 point light gray font, when the smallest they are able to read is 16point. Also, if they have very high resolution monitors, an 8 point font can be tiny.
5. Content actually downloads faster.
6. Content is chunked in such a way that it can be re-used more easily.

The current move to deliver content as Flash-style movies is good for visual animation features, but is bad for accessibility. Also, for sighted users, the visual animations can serve as bad distractions when they are trying to read the content. A focus on the end-users experience (rather than boosting the designer's portfolio) generally results in more accessible and reusable content.

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