The Central Processing Unit
If you look at the motherboard, there is one chip that is much larger than all the rest, usually at least 3 or 4 times as great. This chip is the CPU. It fits into a slot on the motherboard called the socket. The CPU is the 'brain' of the computer. You can tell how important the CPU is from its name. Central – it is the central, most important part of the computer, Processing – it does all the working out and controlling of the computer. In fact, if you were to consider the cost of buying your computer, you would find that much of the money spent was for the CPU. Modern CPUs have more than one controlling chip inside and are thus faster than normal CPUs. Such CPUs are called Dual Core (2 processing chips or cores), Quad Core (4 processing chips or cores) and so on. The speed of the CPU is very important, since the faster this chip is, the faster your computer will be able to function. We measure the speed of the CPU in a unit of frequency called Hertz (Hz) which is a measure of how many processes can be done in a second.