All arithmetical and logical functions within a computer/server configuration are addressed by its Central Processing Unit, or CPU. This hardware part is oftentimes called the "brains" of the personal computer also. The pace at which the CPU carries out system instructions is typically referred to as its speed which is measured in Hertz. The speedier the processing unit is, the faster scripts and web programs will be executed, though the efficiency of the latter is determined by other things also - the read/write speed of the hard disk, the amount of physical memory, the network connectivity, and many others. All new CPUs have a number of cores, that work together. For that reason, the efficiency and the workload which a CPU can tackle increase, due to the fact that each and every core can process different tasks separately and several cores can handle 1 task that can't be processed by 1 core.