All arithmetical and logical functions in a computer/server configuration are addressed by its Central Processing Unit, or CPU. This hardware element is oftentimes called the "brains" of the computer also. The pace at which the CPU runs system instructions is generally referred to as its speed which is measured in Hertz. The faster the processing unit is, the quicker scripts and web applications shall be executed, although the efficiency of the latter depends on other things as well - the read/write speed of the hard disk drive, the amount of physical memory, the network connectivity, and so forth. All newer CPUs have multiple cores, which work together. Because of this, the functionality and the workload a CPU can manage increase, due to the fact that each core can process several tasks separately and numerous cores can handle 1 task which cannot be processed by one core.