CAPTCHA codes are those crazy, squiggly letters that appear for you to type in, ensuring that the response/submission is not generated by a computer, or “bot”. CAPTCHA is a contrived acronym for Completely Automated Public Turing test to tell Computers and Humans Apart. The phrase was coined in 2000 by three Carnegie Mellon University students and one employee of IBM. CAPTCHA codes are used to prevent automated software from performing actions that degrade the quality of a service of a given system. They can also be used to protect systems vulnerable to email spam, and stop automated posting to blogs, forums and wikis. CAPTCHA codes also serve an important function in rate limiting, reducing the speed at which you can continually “try again” to fill out a form or access something, as well as confusing bots that try to guess passwords. Now… if only we could accurately read them!!