In this class, students learn the concept of a UNIX/LINUX system, interface, and programming, and so on. This class also provides practical programming experiences based on the usage of various system resources such as a file, process, thread, network, and I/O. This course is proceeded with lectures given by the instructor. System programming concepts in UNIX are explained with real example codes. Some homeworks are given to students for better understanding of lecture content. Students are evaluated with mid-term, final exam, and programming project.