This document provides an introduction to data mining. It discusses how large amounts of data are now being collected but not fully analyzed, and how data mining can help extract useful knowledge from these vast data sets. The document defines data mining as the non-trivial extraction of implicit and potentially useful patterns from large data sets. It also outlines some common data mining tasks like classification, clustering, association rule mining and regression. Finally, it notes some key challenges in data mining like scalability and high dimensionality.