How do real-time systems differ from normal information systems? Which languages are best for implementing different real-time systems? The fourth edition of this best-selling text on real-time systems answers these and other questions. It provides an in-depth analysis of the requirements for designing and implementing real-time embedded systems, and discusses how these requirements are met by current languages and operating systems. The languages are not only described, but also critically evaluated. No other book on real-time (or concurrent) programming languages covers the same breadth of material.