This book is designed to be suitable for an introductory course at either un- dergraduate or masters level. It can be used as a textbook for a taught unit in a degree programme on potentially any of a wide range of subjects including Computer Science, Business Studies, Marketing, Artificial Intelligence, Bioin- formatics and Forensic Science. It is also suitable for use as a self-study book for those in technical or management positions who wish to gain an understanding of the subject that goes beyond the superficial. It goes well beyond the gener- alities of many introductory books on Data Mining but—unlike many other books — you will not need a degree and/or considerable fluency in Mathematics to understand it.