Like all good web ventures, the Social Web has risen in prominence ahead of any reliable standards that would ensure a consistent user experience. But that's finally beginning to change. With this book, you'll learn about a rich set of open source technologies for building compelling-and secure-social applications and websites. You'll discover what it takes to engage users on a personal level, and learn ways to monetize your venture. Programming Social Applications introduces you to the open source tools used on many major social platforms, and explains how technologies such as OpenSocial, Apache Shindig, OAuth, OpenID, Caja, and others work together to help you solve practical issues. You'll also examine successful proprietary platforms to help you gain a comprehensive understanding of the Social Web's foundations. * Learn how to build viral applications with social data * Implement social web technologies using real-world examples * Work with OpenSocial to standardize social graphs-individual nodes and their relationships * Build a scalable OpenSocial application container with Apache Shindig * Develop comprehensive user authentication and authorization systems using OAuth and OpenID * Learn how Caja, and ADsafe provide user security on social websites * Deal with bugs and other problems when implementing these technologies * Build distributed web frameworks that extend social graphs to include any social footprints users leave on the Web