Design patterns represent the best practices used by experienced object-oriented software developers. Design patterns are solutions to general problems that software developers faced during software development. These solutions were obtained by trial and error by numerous software developers over quite a substantial period of time. This book will take you through step by step approach and examples using Java while learning Design Pattern concepts. This reference has been prepared for the experienced developers to provide the best solutions to certain problems faced during software development and for un-experienced developers to learn software design in an easy and faster way. Before you start proceeding with this book, I'm making an assumption that you are already aware of basic java programming concepts. If you are not well aware of these concepts then I will suggest going through our short book on Java Programming.