Humans can solve them, computers cannot, or so we've been led to believe. Yes, I'm talking about CAPTCHAs, those annoying puzzles you see whenever you post something to Craigslist, or even try to leave a comment on this blog. Originally designed to block spam, Completely Automated Public Turing Test To Tell Computers and Humans Apart, or CAPTCHAs, come in handy in protecting Web sites against bots.
As of this year, 90 percent of e-mail traffic is spam. So anything that helps stop spammers... READ ON