Divided into eight parts, the book tries to provide a comprehensive coverage of topics, beginning with OS architectures and then moving on to process scheduling, inter-process communication and synchronization, deadlocks, and multi-threading. Under the part on memory management, basic memory management and virtual memory are discussed. These are followed by chapters on file management and I/O management. Security and protection of operating systems are also discussedin detail. Further, advanced OSs such as distributed, multi-processor, real-time, mobile, and multimedia OSs are presented. Android OS, being one of the most popular, is discussed under mobile operating systems. The last part of the book discusses shell programming, which will help students perform the lab experiments for this course. The first six parts contain case studies on UNIX, Solaris, Linux, and Windows.