WebAIM -- Web Accessibility in Mind -- is an organization that promotes web accessibility through dissemination of information, tutorials, seminars and workshops.

    Our goal is to improve accessibility to online learning opportunities for all people; in particular to improve accessibility for individuals with disabilities who currently may have a difficult time getting access to postsecondary online learning opportunities.

Particularly eye-opening is the set of simulations (requires Macromedia Shockwave) which allow web developers to experience the particular accessibility issues that vision impaired users encounter. The Screen Reader Simulation helps to understand what it is like for a person with visual impairments to access the Internet using a software program called a "screen reader." The Low Vision Simulation allows you to experience a web page as someone with a visual impairment might see it.

Also of interest is the HTML Markup Sample which provides common accessibility fixes.

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