CPU, or Central Processing Unit, is that part of a computer or a hosting server which carries out all the calculations. Every CPU runs at a particular speed and the bigger it is, the speedier everything shall be processed, so if you host resource-demanding web apps on a hosting server, for example, a powerful processor shall allow them to be carried out much faster, which will drastically contribute to the overall user experience. The new generations of CPUs have two and more cores, each of them operating at a certain speed to ensure a much better and speedier performance. This kind of architecture enables the processor to handle numerous processes at one time or several cores to manage a single process if it requires additional computing power in order to be performed. Of course, other factors including the amount of RAM or the connection a given hosting server uses could also affect the overall performance of the web sites hosted on it.