| CAPTCHA |
| CAPTCHA is the abbreviation of "Completely Automated Public Turing test to tell Computers and Humans Apart". A security measure in the form of displayed random text with distorted fonts, that can be recognized by humans and entered as a response (typically online login) by human users to prevent automated systems from abusing online systems, which do not have OCR capabilites. The term CAPTCHA was designated by by Luis von Ahn, Manuel Blum and Nicholas J. Hopper of Carnegie Mellon University, Pittsburg, PA, and John Langford of IBM in 2000. Sample image shown below, refer [1]. |
| Reference |
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1. Luis von Ahn, Manuel Blum, Nicholas J. Hopper and John Langford. The
CAPTCHA Web Page 2000.
2. Web application and Authentication |
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