Description:
"A 'captcha' is a program that can tell whether its user is a human or a computer [such as those with distorted images of letters]." You can use this site to help stop receiving email spam "by asking people to solve a recaptcha before they can view your email address" (if you are running a web application that lists user's email addresses). This process uses unclear images from digitized books. From Carnegie Mellon University. |