software

The complete computer made up of the CPU, memory and related electronics (main cabinet), all the peripheral devices connected to it and its operating system. Computer systems fall into two broad divisions: clients and servers. Client machines fall into three categories from low to high end: laptop, desktop and workstation. Servers range from small to large: low-end servers, midrange servers and mainframes.A computer system is sized for the total user workload based on (1) number of users sharing the system simultaneously, (2) type of work performed (interactive processing, batch processing, CAD, engineering, scientific), and (3) amount of storage. Following are the components of a computer system and their significance.PlatformThe hardware platform and operating system determine which programs can run on the computer. Every application is written to run under a specific CPU and operating system environment. The most widely used platform means more software is available for it. See platform.Input/OutputA server's input/output (I/O) capacity determines the number of simultaneous users that it can support at terminals or PCs. See channel.Number of CPUs and CoresThe more CPUs, the more processing that can take place at the same time. High-end servers often contain multiple processors. The CPU chip itself may include more than one processor. See SMT and dual core.Clock SpeedThe megahertz or gigahertz rate of the CPU determines internal processing speed. See MHz.Disk and MemoryA computer system's disk capacity determines the amount of information immediately available to all users. Its memory capacity determines how many applications can be efficiently run at the same time.Fault ToleranceThe use of redundant processors, peripherals and power supplies provide continued operation in the event of component failure. See fault tolerant.