Luis von Ahn turns everyone into a crowdsourcer


Depending on your point of view, a CAPTCHA or a reCAPTCHA is either an annoyance (who can read those fuzzy letters, anyway?) or a boon to security, preventing fake account creation, spam commenting, fraudulent transactions, and more.

But did you know that while you’re struggling to click every photo with a traffic light, you’re actually helping Google strengthen its photo recognition software? This is the crowdsourcing genius of Guatemalan-born technology pioneer Luis von Ahn.

The idea for CAPTCHA came in 2000 when then-PhD student von Ahn attended a lecture and learned that Yahoo had a bot problem. Bots were creating millions of free Yahoo accounts to send out spam. To solve the problem, von Ahn co-founded CAPTCHA, a name derived from “Completely Automated Public Turing.” The system required users to type a few characters to prove they’re not robots.

CAPTCHA leads to the birth of reCAPTCHA

But then, von Ahn started pondering how many hours a day were spent solving CAPTCHAs. He wondered how that time could be put to better use. That’s where the idea for reCAPTCHA came from: What if, instead of randomly generated letters, users were given two words—one known and one from a text that needed digitizing? If six users typed the same letters for the second word, it could be considered a match. Genius. Google thought so and bought reCAPTCHA from von Ahn in 2009.

His crowdsourcing experiments didn’t stop there. Von Ahn is co-founder of the free language app Duolingo, which started with a similar premise—teaching English to users for free while they, through the course of their lessons, translated news articles into their native language for paying customers such as CNN and Buzzfeed. Duolingo has moved on from its crowdsourcing translation model, which was its original premise, and the company went public in July with a value of $6.5 billion.

Photo: McLittle Stock / Shutterstock