As government, business, and communications have all moved online in the last decades, cyber security have emerged as a critical priority for organizations of all sizes. New security holes appear when more and more of people’s and businesses’ daily lives move into the digital realm. Cyber security, through a computer scientist’s point of view, is the methods and procedures used to prevent harm to computer programs, networks, and critical data. Cyber security and protective measures are both methods used to limit or eliminate the possibility of intrusion into an information system or a database. Cyber security is sometimes referred to as information security due to its primary function of ensuring data security and privacy. This book covers Introduction to Cyber Technology, Fundamentals of Wireless LAN, Principles of Information Security, Cryptography, Cloud Computing, Cyber Ethics, Hacking, Cyber Crimes, Psychological Profiling, Techniques of Cyber Crime, Security Assessments, Intrusion Detection and Prevention, Computer forensics, Chain of Custody Concept, Cyber Crime Investigation, Digital Evidence Collection, Cyber Law and many more. This book can be guide for all the students and readers who are interested in computer and cyber security. In addition, it is helpful for researchers and scientists working in this promising field.