Book excerpt: Facebook is by far the most popular social networking site, but it is not as user-friendly as the service would like people to think. It leaves many users scratching their heads over even the most fundamental features, such as the difference between their Wall and their News Feed. And Facebook's help system is woefully inadequate. The Complete Idiot's Guide® to Facebook, Third Edition, gets readers registered and touring Facebook in the very first chapter and never lets up as it reveals the features that have made Facebook so amazingly popular. Users discover how to: - Flesh out and protect the all new personal profile - Track down long lost friends, family members, and classmates - Communicate via status updates, email, and chat - Share photos and video - Make the best use of the new Timeline feature - Take advantage of Facebook's new location-based functionality - Schedule real world get-togethers and send out invitations - Share common interests in groups - Play games - Understand Facebook's dizzying array of privacy options that dictate who sees one's content - Buy and sell stuff in the Facebook Marketplace, and more. Readers also learn how to tap the power of Facebook for more than simply personal use-such as personal branding; marketing a business, product, service, or non profit; or promoting a worthy cause.