What do Amazon's product reviews, eBay's feedback score system, Slashdot's Kharma System, and Xbox Live's Achievements have in common? They're all examples of successful reputation systems that enable consumer websites to effectively manage and present user contributions. With this book, you'll learn how a reputation system can enhance your business, and what it takes to design and develop your own. If you're building, operating, or participating in a website or online application, you'll discover why these underlying mechanisms are critical for any organization that plans to include user-generated content on a website. Learn how to scale your reputation system to handle an overwhelming inflow of user contributions. Become familiar with different models that help you encourage first-class contributions. Quickly determine the quality of contributions, and learn why some are more useful than others. Discover tricks of moderation, including how to stamp out the worst contributions in a quick and efficient way. Learn to engage contributors and reward them in ways that get them to return again and again.