All arithmetical and logical procedures in a computer/server configuration are addressed by its Central Processing Unit, or CPU. This hardware part is sometimes called the "brains" of the computer system as well. The rate at which the CPU completes system instructions is also referred to as its speed and it is measured in Hertz. The quicker the processing unit is, the faster scripts and web applications shall be executed, even though the overall performance of the latter depends on other things also - the read/write speed of the hard drive, the amount of physical memory, the network connectivity, and so forth. All newer CPUs have multiple cores, that work together. For that reason, the functionality and the workload that a CPU can tackle increase, due to the fact that every single core can process a number of tasks individually and numerous cores can handle one task which can't be processed by a single core.