When building or upgrading a PC, there's one component that is arguably the most important, serving as your system's foundation. This is, as you may have guessed, the motherboard. Your choice of motherboard will determine many things in your build, such as the components you are able to use, and vice versa - for example, your choice of CPU may determine which motherboard you should purchase. So, what exactlyis a motherboard, and what should you look out for? Read on for our top tips.