(Formerly numbered 117.) (Same as Computer Science M138.) Lecture, four hours; laboratory, one hour; outside study, seven hours. Requisite: Computer Science 33. Recommended requisite: Computer Science 111. Introduction to fundamental knowledge of computer system security. Students gain understanding of exploit techniques; learn to use the security tools; learn to design and implement secure systems; and learn concepts of computer security including software vulnerability analysis and defense, web security, mobile security, and network security. Covers the latest security topics in practice (e.g., cryptocurrency), and in research (e.g., state-of-the-art fuzzing techniques and machine-learning-based security analysis). Students get hands-on experience in analyzing and designing secure systems. Includes course project for cutting-edge security research. Letter grading.