Structured to cover—Operating Systems (OS) Concepts, Practice, and Instructional Projects—the Fifth Edition of the book aims to provide a practical view of GNU/Linux and Windows 7, 8 and 10, covering different design considerations and patterns of use. The section on concepts covers fundamental principles, such as file systems, process management, memory management, input-output, resource sharing, interprocess communication (IPC), distributed computing, OS security, real-time and microkernel design. This thoroughly revised edition comes with a description of an instructional OS to support teaching of OS. Sections dealing with FEDORA, a variant of Linux, describe the essence of digital asset management. The book also covers Android, currently the most popular OS for handheld systems. Basically, the book aims to enable students to learn by practicing with the examples and doing exercises. This book is intended to cater to the needs of the students of Computer Science/Engineering, Computer Applications and Information Technology. As the knowledge of Operating Systems is essential for the IT practitioners, this book also caters to the needs of those who might not have had a formal Computer Science/Engineering education or training for updating their knowledge on contemporary OS design.