As you may already know by now, Captcha is a common approach to prevent access of users that aren’t human to all kinds of websites. The captcha is a kind of test that requires verification of distorted image plus textual content which is deciphered easily by humans but not by computer bots. 
However, it appears that [...]

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Is the Captcha test not perfect? It sure looks like it can be improved, as not too long ago some bot spammers had succeed to crack the Captcha codes of the registration process to Gmail…

Captcha service protects websites and navigators from robot spammers which spider the web to accumulate emails or registration to sites like forums and blogs…

An advertising network is a group of online advertisers and publishers connected by an agency that allows them to use its online platform for ads exchange…

Recaptcha is a system which uses Captchas to digitalize books text and pages in order to ensure the user is not a computer or robot but a human being.