Launched in private beta in November 2011, Duolingo has accumulated over 300,000 users in waiting list. On June 19, 2012, the company was launched for the general public and had more than 10 million users since then.
Duolingo’s education models are dictation and written lessons, although there is less practice speaking. Word meanings can also be learned through the vocabularysection. Progress is monitored using a gamified skill tree.
As languages are learned, users receive “skill points.” a skill is considered “learned” when all associated lessons have been completed. For each completed lesson, users earn 13 points.