Duolingo, Inc. builds and operates an online platform and a mobile application dedicated to language learning, catering to audiences in both the United States and China. The company's comprehensive curriculum spans 40 diverse languages, featuring prominent options such as Spanish, English, French, Japanese, German, Italian, Chinese, and Portuguese, among others. Furthermore, it offers a digital examination for assessing language proficiency. This enterprise was founded in 2011 and its main offices are located in Pittsburgh, Pennsylvania.