Human Computation, Crowdsourcing, and the brilliance of Luis von Ahn 


Ever used Duolingo? I brushed up on my Spanish with it a few years ago. It was an incredible program that best of all was free. However, it is a for-profit company. How does Duolingo make money? It’s business model is an extension of its brilliant co-founder, inventor, and young professor, Luis von Ahn. Von Ahn invented the captcha.


You know what these are. They are the little prompts that ask you to type the distorted word on the screen to prove that you are a human. These little security devices are used about 200 million times a day. Von Ahn’s brilliant idea was to use these 200 million different little human efforts, each lasting about ten seconds (over 500,000 hours day in total), to produce something meaningful. He invented the re-Captcha, which makes it so that each time you type in a word or two to prove you are human you are also translating a scanned book into digital form. In other words, Von Ahn is using “human computation,” which is the combination of human brainpower with the power of computers to solve real world issues not able to be solved by humans or computers alone. You can learn more about this in the video.


Duolingo is an extension of the idea of crowdsourcing in which a large number of people provide input and effort towards a task, usually accomplished through the internet. As part of its learning program Duolingo has its members translate articles or parts of articles that are later sold to companies such as ESPN and CNN. In return for your free foreign language program you produce a little bit of work for Duolingo. When enough members have a shared translation the document is considered to possess a high level of probability that it is translated correctly. You are not only a translator and a learner, you are also a proofreader. Duolingo combines the efforts of many beginning language learners into a product that is equal to the work of a single professional translator. Amazing isn’t it?

The attached video is entertaining and inspiring to watch. It tells the story of the founding events and ideas behind Duolingo. It also demonstrates the genius of Luis von Ahn and his project to combine human efforts, with the help of the internet, into large scale projects that were previously unimaginable.

I am already thinking about jumping back into Duolingo and learning another language. By the way, Duolingo also uses a cyclical teaching style in which words and phrases are recycled throughout the program to build long term retention. Duolingo continually tests your previous knowledge and uniquely adapts your learning based on your scores.

Hope you enjoy the video and that is inspires you.

You can access the video here. 

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