At some point, Luis found out that Yahoo had a problem with spammers who were abusing their systems and Yahoo had no way to stop them. Luis and his advisor invented Captcha to stop these spammers.

These are games that humans play willingly and in the process help computers to solve problems that computers cannot solve otherwise.

Captcha is one of the examples. Crossword puzzles is another.

First, Luis was not making any money of captchas. He was just an academic, happy that someone was actually using his creation. Later, he ended up building a small commercial version of captcha and selling it to Google, a product that became the Google Image Labeler.

By 2006 however, captcha was widely used on the internet, and this time Luis started a massively profitable company called Recaptcha. Every time someone was typing in a short segment of captcha, on the back that action was actually digitizing printed text. Meanwhile, companies like New York Times and Google were paying Recaptcha for every input.

Luis is originally from Guatemala, a very poor country where rich people are able to afford the best education, while poor struggle to get any. As a result, the rich continue to be rich, and the poor are poor.

Luis wanted to give everyone equal access to education.