This lecture covers the internals of scheduling in computer systems, tracing its origins back to operations management. It discusses the scheduling policy, which determines the order of process execution, and the importance of the idle process, which runs when no other processes are ready. The instructor explains scheduling metrics, focusing on CPU utilization and turnaround time, emphasizing the goals of maximizing efficiency and minimizing job completion time. Simplifying assumptions are introduced to facilitate understanding of scheduling policies, including the notion that all jobs arrive simultaneously and run to completion without interruption. The lecture also touches on the complexities of scheduling in modern systems, including overlapping I/O and multi-core architectures, while noting that a foundation in queuing theory is essential for a deeper understanding of scheduling. The instructor concludes by highlighting the challenges posed by multi-threaded applications and the intricacies of scheduling in contemporary computing environments.