Contents: 1. Introduction. 2. Operating system services. 3. Process management. 4. Multithreading and scheduling. 5. Synchronization. 6. Memory management. 7. File system and storage. 8. Input output systems and security. 9. Signals. 10. POSIX threads programming. 11. Numeric problems. 12. Theoretical questions This book has been specifically designed to orient students for the technical interview in Operating System concepts. This book has been written to help students undertake a thorough and objective preparation. The contents have been carefully handpicked from authors' experience and expertise developed by being either direct witness to the recruitment process, mentoring students in their colleges, myriad discussion with peers who are placement organizers in colleges, hours of studying discussions on the topics in social media, blogs and dedicated web sites, and so it is no wonder that the book is highly focused for interview preparation in Operating System. This book includes the latest topics and questions discussed in top companies today while continuing to maintain the emphasis on basic concepts along with problem solving skills for both students preparing for exams and for interviewees.