This book gives a complete introduction to cybersecurity and its many subdomains. It’s unique by covering both technical and governance aspects of cybersecurity and is  easy to read with 150 full color figures. There are also exercises and study cases at the end of each chapter, with additional material on the book's website. The numerous high-profile cyberattacks being reported in the press clearly show that cyberthreats cause serious business risks. For this reason, cybersecurity has become a critical concern for global politics, national security, organizations as well for individual citizens. While cybersecurity has traditionally been a technological discipline, the field has grown so large and complex that proper governance of cybersecurity is needed. The primary audience for this book is advanced level students in computer science focusing on cybersecurity and cyber risk governance. The digital transformation of society also makes cybersecurity relevant in many other disciplines, hence this book is a useful resource for other disciplines, such as law, business management and political science. Additionally, this book is for anyone in the private or public sector, who wants to acquire or update their knowledge about cybersecurity both from a technological and governance perspective.