# reCAPTCHA and Duolingo Founder Luis von Ahn ## Podcast - Resouces - [reCAPTCHA and Duolingo: Luis von Ahn](https://www.npr.org/2020/05/22/860884062/recaptcha-and-duolingo-luis-von-ahn) from How I Built This - [Meet Luis von Ahn, the Guatemalan immigrant behind the world's most popular language app Duolingo](<https://abcnews.go.com/International/meet-luis-von-ahn-guatemalan-immigrant-worlds-popular/story?id=93122372>](<https://abcnews.go.com/International/meet-luis-von-ahn-guatemalan-immigrant-worlds-popular/>) from abcNEWS - What was behind Luis' early desire to become a Math professor and why did Luis switch from Math to Computer Science? - Luis was a math nerd. By doing math research he doesn't need to deal with people. - Describe the problem posed by the _Yahoo!_ Chief Scientist at a talk that Luis went to, the solution that Luis and his advisor came up with, and how much money he made on it. - There are people out there registering large amounts of email addresses using computer program. - Let computer generate distorted letters and digits that computers cannot read but human can. - He didn’t make anything – Luis just gave the code to Yahoo. - Describe the "game" that Luis developed as part of his PhD research, and who bought the technology. - "Finding things that computers cannot do but human can." - Go to website, randomly paired with another, you are shown the same picture, now type the word you think the other people is typing. – This creates labels for the image. - Google bought this technology. - Describe Luis' rationale for why his captcha technology needed to have people do something useful in solving the captcha. - People spent so much time solving CAPTCHA, can we let them do some meaningful work out of this? - Describe how Luis' first company came out of a project digitizing old issues of The New York Times, who bought the company, and what amount of the money went to investors. - $42k for every year of content for New York Times. - Luis can’t take checks directly from The New York Times; hence he started a company. - Google bought this. - 5% of the money went to CMU, others all went to Luis himself. - Describe the problem that Luis and PhD student Severin Hacker come up with to work on. - Do something that gives education for free to the poor. - Describe the "right-place-at-the-right-time" moment for DuoLingo. - Connected with venture capitalists. - Describe the "biggest fool" moment Luis encountered in raising venture funds, the standard ways of making money from an app, and how DuoLingo settled on a way to make money. - DuoLingo didn't had any plan to make money at the beginning. - Typical ways of making money: ad, pay-wall, selling user data. - Ended up adding ads – then subscription to turn off ads. - What did Luis attribute to DuoLingo's success over other language learning tools like Rosetta Stone and why? - It's free. - Other apps are crappy. - DuoLingo teaches you really well from beginning to intermediate level. - What was the most meaningful insight for you personally from Luis's story? - Think differently, identify the key problem, explore what is fun. - What is the current estimated current market cap for Duolingo? - $6.75B