CPU, that is oftentimes called just "processor", is an abbreviation for Central Processing Unit. This is the core of every personal computer or server, as it runs all the calculations and logical input/output procedures. Though the performance of a site or an app relies upon other things as well, including the amount of physical memory or the online connectivity of the hosting server, the rate at which a given processor works determines how soon an app will be executed. Later-generation processors have several cores which can significantly improve their overall power and efficiency, as each and every core can manage a variety of processes individually or several cores can handle one process that needs a considerable processing power. Due to the fact that every core runs at a certain speed, this architecture can be looked at as a number of independent processors cooperating.