The Two Words

Type the two words:

Ah, CAPTCHA. That Completely Automated Public Turing test to tell Computers and Humans Apart. Many just know it as the annoying text box that they have to get past to do several things on the internet. CAPTCHA actually traces its roots back to the beginning of the internet, and computer hackers.

In the beginning, users wanted to create text that was illegible to computers. The first hackers, wanting to post sensitive information without being caught by filters, would change characters in text (such as changing the E in “hello” to a 3, so the word would read “h3llo”). This procedure became popular, and would later come to be known as leetspeak (which would infect the world of gaming). The term “CAPTCHA” was coined in 2000 by Luis von Ahn, Manuel Blum, Nicholas Hopper, and John Langford, and the most common form of CAPTCHA was developed by Mark D. Lillibridge, Martin Abadi, Krishna Bharat and Andrei Z. Broder. This form involves a distorted word, image, or digits. CAPTCHA was originally developed as a sort of gateway, preventing computer bots from entering certain parts of the net. This could include sensitive data, preventing programs from mass creating accounts for websites, or downloading large quantities of data.

The CAPTCHA system was refined into commercial systems, one of which being reCAPTCHA. It uses the same word recognition system, in the form of two word prompts. This system not only prevents bots (working with two distorted words instead of one), but it also helps digitize the text of books. The reCAPTCHA service is a subscription service, supplying websites with images and words that cannot be read by recognition software. Businesses pay for the service to use in their validation procedures, and in turn the results of the test are sent back to reCAPTCHA to help with digitalization projects. reCAPTCHA has worked on digitizing archives of the New York Times, and as of 2012 has digitized 30 years of the magazine. Acquired by Google in September of 2009, the system’s slogan has become “Stop spam, read books”.

While CAPTCHA seems to escape most when thinking of frequent web technologies, it is more relevant than most think. Websites that use the system include Facebook, CNN.com, and Ticketmaster. CAPTCHA reports that it displays over 100 million CAPTCHAs every day, showing how widespread the system is. While we are all humans (at least, I hope so), this system helps security on a wide range.

From computer hacking to stopping thousands of computer bots, what are the chances?