Please note that the content of this book primarily consists of articles available from Wikipedia or other free sources online. Rules of Play: Game Design Fundamentals is a book on game design by Katie Salen and Eric Zimmerman, published by MIT Press. The book is divided into four units, first introducing core concepts, then expanding on these with a detailed discussion of rules, play and culture. Unit 1: Core Concepts Meaningful play - The authors introduce the concept of meaningful play as the goal of successful game design, providing their own definitions. Design - The authors discuss definitions of design, and introduce their own. They go on to discuss semiotics, the study of meaning, describing Charles Sanders Peirce''s semiotic elements.