1 A Personal Computer
Figure 1 shows an old advertisement for a laptop from about 2010. The main features of the computer are listed in this advert. One item on the list is ‘Processor: AMD E450 1.65 GHz’. So this computer uses an AMD E450 processor, running at a speed of 1.65 GHz. A processor is an essential component of a computer; it carries out, or executes, the instructions that make up the computer program. PCs use one main processor and several other ‘supporting’ processors, and adverts for PCs often specify what main processor they use. The speed of the processor (1.65 GHz in this instance) is a measure of how fast the processor can carry out each instruction. (Don’t worry if you don’t understand the term ‘GHz’ and other specialised terms used in the advert such as ‘Ram: 6gb DDR3’. These will be explained as the course progresses.)