The book addresses the fundamentals and legal aspects of modern IT systems, as well as their implementation in various applications, with particular emphasis on data protection. It specifically focuses on the connection between data protection and data security, which is becoming increasingly important in the emerging information society. The rapid spread of the internet and the security-critical applications built upon it are particularly relevant in this context. This complexity makes the tasks of corporate and institutional security officers more challenging and increasingly important. The book illustrates how to plan and implement extensive investments in data protection-compliant security measures. It also highlights the significance of mutual understanding and joint discussions between legal experts and technicians, as recognized by the developers.