Duolingo was created in 2009 in the United States by two computer scientists. Luis von Ahn, 30, is a professor of computer science at Carnegie Mellon University.
He co-invented Captcha, a security measure used by websites for an Internet user to prove that he is not a robot. He believes his incredible success is due to the English lessons he received from an early age, in Guatemala City. He was able to attend an American private school in his country, then come to study in the U.S at the age of 18.