CAPTCHAs May Do More Harm Than GoodIf an annoyance contest were held between passwords and CAPTCHAs, passwords would probably win, but not by much. CAPTCHA -- Completely Automated Public Turing Test To Tell Computers and Humans Apart -- was created to foil bots attempting to mass-create accounts at websites. Once created, those accounts could be exploited by online lowlifes for malicious ends, such as spewing spam.
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CAPTCHAs May Do More Harm Than Good