I was recently forwarded a link to ReCaptcha, and was stunned to realize that I have never written about it.  Stunned because ReCaptcha was one of the main sparks of my interest in crowdsourcing.

ReCaptcha is a tool out of Carnagie Mellon, headed by Luis von Ahn (mentioned previously here).  To understand reCaptcha, one needs to understand captchas.  A captcha is a human verification tool that displays an image with a string of warped characters.  The task is to write those characters into the input box.  Because of the complexity of image recognition, this task more or less confirms that you are a human and not a bot. Of course, spammers can hire low-wage captcha crackers, but captchas nonetheless introduce an enormous hurdle to online spam and other automated cons.

ReCaptcha is an improvement on the original concept.  Amongst other accessibility improvements, reCaptcha’s primary innovation is that it helps digitize old books.  That right, digitize old books.  Rather than offering randomly warped words, reCaptcha instead offers the user words from scanned books that the computer recognition is having trouble with.  This assists in the various efforts to digitize (and in the process preserve and recover) libraries of aging books.

The brilliance of this cannot be understated.  The tool takes an action that millions of people already need to do, and appropriates that manpower into something useful.  Perhaps the best parallel is to solar energy.  The sun is an energy source that is completely wasted in urban areas.  It is everywhere, constantly beaming this energy onto the earth, and the cleverness of solar cells allow is for people to capture this potential (constant and wasted) and convert it to something greatly useful.  Anybody who has ever been awed by solar energy can understand the exciting potential that reCaptcha represents in technology.