All arithmetical and logical functions inside a computer/server configuration are addressed by its Central Processing Unit, or CPU. This hardware part is oftentimes called the "brains" of the PC as well. The pace at which the CPU carries out system instructions is also referred to as its speed which is measured in Hertz. The faster the processing unit is, the faster scripts and web programs shall be executed, although the overall performance of the latter depends on other things too - the read/write speed of the hard disk drive, the amount of physical memory, the network connectivity, and so on. All new CPUs have several cores, that work together. Subsequently, the functionality and the workload that a CPU can manage increase, as every single core can process various tasks individually and numerous cores can handle a single task which cannot be processed by 1 core.