All arithmetical and logical operations in a computer/server configuration are handled by its Central Processing Unit, or CPU. This hardware component is occasionally called the "brains" of the personal computer as well. The pace at which the CPU carries out system instructions is commonly referred to as its speed which is measured in Hertz. The swifter the processing unit is, the speedier scripts and web programs shall be executed, although the efficiency of the latter depends upon other things as well - the read/write speed of the hard disk drive, the amount of physical memory, the network connection, etc. All newer CPUs have several cores, that work together. Thus, the efficiency and the workload that a CPU can tackle increase, because each core can process several tasks individually and numerous cores can handle a single task that cannot be processed by 1 core.