Short for Completely Automated Public Turing test to tell Computers and Humans Apart, CAPTCHA is a protection that identifies humans from computers. A commonly used CAPTCHA is an image that is distorted that contains text that is easy for humans to read, but difficult or impossible for computers to read. The picture is an example of a CAPTCHA.
In the picture, the visitor can visually identify the words "overlooks" and "inquiry" to validate they're human. Without this information being entered into the web page, a user would be unable to continue. Unfortunately, blind or hard of seeing visitors run into difficulties with CAPTCHAs because of the inability to read the letters shown in the image. To help these visitors gain access to a page protected by a CAPTCHA, an audible CAPTCHA will read the letters aloud to the visitor.
Are CAPTCHA's case sensitive?
No, a CAPTCHA is not case sensitive, so if the same words mentioned earlier were entered in uppercase it would still work.
How is CAPTCHA pronounced?
CAPTCHA is an acronym that is sounded out. So, it would be pronounced as cap-cha.