For years, many websites tried to block spammers and bots by making Web users read a distorted series of characters and asking them to type back what they saw, as a way to verify it was a human entering the site. The theory behind these CAPTCHA boxes is that what machines see as gobbledygook, humans can still decipher. In April, however, research from Google showed that computers are just as good at defeating these security systems. Now sites that have adopted Google’s new human-verification system will only require you to check a box saying “I’m not a robot.” Don’t get too excited yet though, those CAPTCHA boxes will still show up when Google's algorithm decides it needs extra proof beyond the checkbox.