This is volume 76 of the Advances in Computers. Since 1960, annual volumes are produced containing chapters by some of the leading experts in the field of computers today. For almost 50 years these volumes present ideas and developments that are radically changing our society. One of the most important ideas sweeping though society today is the social networking website. Names like Wikipedia, Flickr, Second Life, Twitter, Facebook, Meetup, My Space, Linked In, among others, are becoming common parlance as the youth, and a growing segment of the adult population, now view such websites as alternatives to the corner convenience store or coffee shop and critically important avenues for social interactions. In this volume we explore this phenomenon to describe the development of some of these ideas as well as developments in web technology that enable this to occur. This volume contains seven chapters divided into two parts. The first three chapters describe the social networking phenomenon and provide insights into the technology and influences on our culture. The last four chapters provide details of the underlying technology that allows the web to expand to include these social networking sites, as well as other new applications for information dissemination, accessing, and sharing.