viii As we look for such a strategy, technological development races on with new technologies that make our efforts and existing technologies on which they are based obsolete in shorter and shorter periods. For example, when I started to write the first edition in 1996, computer networking and associated computer network security were not big, the Internet and associated d- coms were yet to become commercialized and associated with big money, and mass global computer network attacks like âMalissaâ, âLove Boyâ, and Distributed Denial of Services (DDOS) were unknown. All these illustrate the speed at which the computing environment is changing and demonstrate a need for continuous review of the computer s- ence education in both content and pedagogy. So the focus in this edition is to address those changes. In this edition, I have made major changes in some of the chapters, reorganized others, and added new ones to bring the book update with current issues.