Duolingo is a very popular language learning application for mobile platforms. It offers easy-to-learn courses in various languages. It is designed to be user-friendly, interactive, fun and effective, making it easy for anyone who wants to learn a new language at their own pace.

Due to work needs or personal hobbies, we may need to learn different languages. Although there are plenty of textbooks and courses available for this purpose, in today's age of mobile networks, digital education has created a more comfortable, easy, enjoyable and efficient way and environment for us to learn languages. At the same time, there are many language learning programs, but few of them are really scientific, effective, fast or interesting.