CPU, or Central Processing Unit, is that part of a PC or a server that runs the calculations. Each CPU runs at a specific speed and the larger it is, the quicker everything will be processed, so if you host resource-demanding web apps on a web server, for instance, a powerful processor will enable them to be executed quicker, which will significantly contribute to the overall user experience. The new generations of CPUs have two and more cores, each one functioning at a specific speed to guarantee a much better and swifter performance. Such architecture enables the processor to control numerous processes all at once or several cores to manage one process if it requires extra computing power in order to be completed. Needless to say, other variables like the amount of RAM or the connection that a given web server uses could also affect the performance of the sites hosted on it.