CPU, that is oftentimes called just "processor", is an abbreviation for Central Processing Unit. This is the core of every laptop or computer or web server, due to the fact that it carries out each of the calculations and logical input/output procedures. Although the performance of a site or an app relies on other things too, including the amount of physical memory or the connection of the web server, the speed at which a given processor performs determines how quick a program shall be executed. Later-generation processors have multiple cores which can seriously increase their overall power and efficiency, since each core can take care of several processes separately or a number of cores can handle 1 process that requires a significant processing power. Since each core runs at a particular speed, this architecture can be seen as numerous independent processors cooperating.