This overview examines significant real-time scheduling policies in use in applications such as flight control, telecommunication systems, nuclear plant supervision, and surgical operation monitoring. The bases of real-time scheduling and its major evolutions are described using unified terminology and notations, covering centralized computing systems, some distributed systems, and local-area and larger networks. With chapter exercises, answers, and cases the book is useful as a text for university students in computer, software, electronics, and control system engineering, and as a reference for engineers and developers in the systems and communications industry.