“At first, it made me feel good to look at the impact my research has had,” says von Ahn, who grew up in Guatemala.
Then he did the math: “It takes about 10 seconds to type each Captcha. I realized that humanity as a whole is wasting 500,000 hours every day typing Captchas.”
When von Ahn compared that to the 7 million hours it took to build the Empire State Building or the 20 million hours spent constructing the Panama Canal, he wondered, “Is there a way we can make good use of this time?”
In 2007, he came up with reCaptchas. Now, instead of frittering away their time typing random characters, Internet users spell actual words plucked from old books that computers have trouble reading.
The Open Content Alliance, a nonprofit group based in a San Francisco, has enlisted about 150 libraries and research centers to digitize as many printed works as it legally can and post them online for anyone in the world to read.
“Everything on the Internet Archive [archive.org] is free to use and free to download,” says Gabe Juszel, coordinator for the project’s largest scanning center that occupies a dim office at the University of Toronto. “We want to make sure a person in China has the same resources as a grad student here at U of T. After all, there are more Internet cafes than there are libraries in the world.”