The prime objective behind publishing this book is to increase the awareness on cybersecurity. The chapters are organized incrementally by subject. Chapter One is a brief introduction to basic concepts of systems, information systems, threats, and risk. It also gives a general overview of the terms that are going to be used. Chapter Two presents the overview of application layer security per the OSI model of computer networks. It also discusses several secondary data-storage media and their mechanisms, archival, and retrieval systems. Concerns about intrusion detection systems, virtual private networks, electronic transactions, and cryptography are also covered. Chapter Three introduces the implementation of security during each and every phase of the system development life cycle. In this chapter we also discuss the concept of physical security on IT assets. Chapter Four deals with laws related to the cyber world. This book should appeal to a wide audience as an effective self-study guide.