Working with big data using data mining tools is rapidly becoming a trend in education industry. The combination of the current capacity to collect, store, manage and process data in a timely manner, and data from online educational platforms represents an unprecedented opportunity for educational institutes, learners, educators, and researchers. In this position paper, we consider some basic concepts as well as most popular tools, methods and techniques regarding Educational Data Mining and Learning Analytics, and discuss big data applications in language learning, in particular.