CAPTCHA is a program that is designed to differentiate humans from bots, and is widely adopted in many websites to prevent spam or other malicious activities. Usually, such a program involves matching the characters in a picture, or selecting a few pictures from a group. Some research indicate that the world wastes around 500 years worth of time on solving CAPTCHAs every day.
Recently, a research conducted by Gene Tsudik at the University of California, Irvine, and his colleagues showed that bots nowadays have little to no trouble passing these tests using less time than humans do, thus making these tests somewhat obsolete.
The research involved having 1000 people perform CAPTCHA tests on some of the world's most popular websites, and compare their performances to that of bots coded by researchers and published in journals. It turned out that the bots can solve the puzzle in less than a second with almost a 99% accuracy, whereas humans need around 10 seconds to complete a CAPTCHA with a mere 50% to 84% accuracy.