This book is directed at practitioners and decision-makers in libraries as well as information specialists who wish to familiarize themselves with folksonomies and social tagging or who must decide whether to implement this type of user-generated content annotation at their organization. The book explains the use of folksonomies and social tagging principally through the presentation of successful real-world examples, and provides descriptions of success factors, along with checklists for implementation. These suggestions are preceded by a detailed introduction to user-generated content classification by means of folksonomies, together with a discussion about their advantages and disadvantages.