Accessibility of Captcha
Captcha is a technique that is increasingly used on websites for web/ signature authentication. You're probably familiar with the box of squiggley letters and numbers that one is asked to type in correct sequence. This is a captcha technique. However, for many users who have certain disabilities, this can be difficult -- if not impossible -- to complete. To read more of the technical discussion, visit http://www.w3.org/TR/turingtest/