CPU, that's sometimes called just "processor", is an abbreviation for Central Processing Unit. This is the core of each computer or hosting server, due to the fact that it carries out all of the calculations and logical input/output procedures. Despite the fact that that the performance of a site or an application is determined by other things as well, like the amount of physical memory or the connectivity of the server, the pace at which a given processor performs determines how fast an app will be executed. Later-generation processors have a number of cores that can considerably boost their overall power and efficiency, since each core can take care of a number of processes independently or a few cores can take on one process which needs a significant processing power. Since each and every core operates at a particular speed, this architecture can be looked at as a few independent processors working together.