Using CAPTCHA technology: pros and cons. Ways to secure from spam-bots attacks.
This paper is devoted to CAPTCHA technology. Algorithms of creation and work of captcha are described. The scheme of how captcha works is also included. The means of encoding and ‘complication’ of decoded text are described. The main ways of automatic captcha’s recognition are described. Also, it is given in examples options of CAPTCHA’s tests. The programing means that do not require user’s actions are considered. By the way, pros and cons of testing captcha are analyzed. In addition, the main problems that may occur during developing captcha are analyzed.