With the unprecedented rate at which data is being collected today in almost all fields of human endeavor, there is an emerging economic and scientific need to extract useful information from it. Data mining is the process of automatic discovery of patterns, changes, associations, and anomalies in massive databases. This book will provide an introductory survey of the main topics in data mining and knowledge discovery, including: classification, clustering, association rules, sequence similarity, and so on. Emphasis will be laid on performance and implementation issues, as well as on applications such as web mining.