系统不仅仅只是硬件.系统是硬件和系统软件相互交织的集合体,它们必须共同协作以达到运行应用程序的目的.

The System is not only just hardware. System is collection of intertwined hardware and system software, they must cooperate together and arrived goal of run application program.

在数字计算机的整个历史当中,有两个需求是驱动进步的持续动力:一个是我们想要计算机做得更多,一个是我们想要计算机运行得更快.当处理器能够同时做更多事情是,这两个都会改进. 术语并发是一个通用的概念,,指一个同时具有多个活动的系统;术语并行指的是用并发来使一个系统运行得更快.并行可以在计算机系统的多个抽象层次上运用.

Throughout the history of digital computer, have two demands are constant force of driving improvements: we want the them to do more, we want them to run fast. Both they will improve when the process can do more thing. Term concurrency is general concept, we use it refers to a system with multiple activities at the same time; Term parallelism refer to use concurrency let system run faster. parallelism can be exploited at multiple abstraction levels in computer system.