The frequency of new editions of this book is indicative of the rapid and trem- dous changes in the fields of computer and information sciences. First published in 1995, the book has rapidly gone through three editions already and now we are in the fourth. Over this period, we have become more dependent on computer and telecommunication technology than ever before and computer technology has become ubiquitous. Since I started writing on social computing, I have been ad- cating a time when we, as individuals and as nations, will become totally dependent on computing technology. That time is almost on us. Evidence of this is embodied in the rapid convergence of telecommunication, broadcasting, and computing devices; the miniaturization of these devices; and the ever increasing storage capacity, speed of computation, and ease of use. These qualities have been a big pulling force sucking in millions of new users every day, sometimes even those unwilling. Other appealing features of these devices are the increasing number of applications, apps, as they are increasingly becoming known, and being wireless and easily portable. Whether small or big, these new gizmos have become the c- terpiece of an individual's social and economic activities and the main access point for all information. Individuals aside, computing technology has also become the engine that drives the nations' strategic and security infrastructures that control power grids, gas and oil storage facilities, transportation, and all forms of national communication, including emergency services.