This course provides a comprehensive introduction to system security, with a special focus on operating system security. Students will start with an overview of computer security, including an introduction to basic principles and concepts, and an understanding of common security threats and attacks. Students will learn about the structure and components of operation systems (OS), types of threats specific to OS, access control and authentication mechanisms, and security policies and models relevant to OS. Furthermore, they will delve into the protection mechanisms at the OS level, such as memory and file protection, secure boot, and sandboxing, and understand how to detect and prevent intrusion at the system level (intrusion detection and prevention). The course also covers other important areas of systems security, such as secure program development, database and data security, and privacy and anonymity considerations in computer systems.