All arithmetical and logical procedures in a computer/server configuration are handled by its Central Processing Unit, or CPU. This hardware element is typically called the "brains" of the personal computer too. The rate at which the CPU completes system instructions is commonly referred to as its speed which is measured in Hertz. The quicker the processing unit is, the faster scripts and web programs shall be executed, although the general performance of the latter depends on other things too - the read/write speed of the hard drive, the amount of physical memory, the network connection, etc. All current CPUs have numerous cores, that work together. Subsequently, the overall performance and the workload a CPU can handle increase, because every core can process a number of tasks independently and several cores can handle a single task which cannot be processed by one core.