CPU, that's frequently called just "processor", is an abbreviation for Central Processing Unit. That is the core of each computer or web server, as it performs each of the calculations and logical input/output operations. Despite the fact that that the performance of a site or an application relies on other things also, including the amount of physical memory or the connection of the web server, the pace at which a certain processor operates determines how quick a program will be executed. Later-generation processors have numerous cores that can severely boost their overall power and efficiency, because each and every core can take on a number of processes independently or a few cores can handle one process which requires a considerable computing power. As every single core runs at a certain speed, this architecture can be seen as a few independent processors working together.