All arithmetical and logical procedures inside a computer/server configuration are handled by its Central Processing Unit, or CPU. This hardware component is oftentimes called the "brains" of the computer as well. The rate at which the CPU executes system instructions is usually referred to as its speed and it's measured in Hertz. The faster the processing unit is, the more quickly scripts and web programs shall be executed, although the overall performance of the latter depends upon other things also - the read/write speed of the hard disk drive, the amount of physical memory, the network connectivity, and so forth. All current CPUs have numerous cores, which work together. Thus, the efficiency and the workload that a CPU can tackle increase, since every single core can process different tasks individually and several cores can handle 1 task that cannot be processed by 1 core.