Hardware is the physical part of the system. This, for the most part, will be a PC. However there is more to it than that. If more than on PC is required then maybe a network will be needed. What about different input or output devices such as a barcode reader or a scanner. It may even require more specialist hardware such as a computer controlled lathe or manufacturing line. The choice of PC in these cases is the least of your worries.

When deciding on what hardware to use there will always be a cost issue to consider. The more powerful the PC the better the software will run but there will be a point where the speed of the PC will not make a dramatic difference to the performance of the system. For example a system which is used by only 10 people would not require a hugely expensive PC while a 1000 person system would require a much more powerful system.

It is very important to consider how information will be taken into the systems and also taken out of the system; the inputs and the outputs. Automating input and output is a good way of meeting requirements. As a example consider a electronic point of sale (EPOS). The operator could easily enter the prices of items manually. They could, also, use a barcode scanner. Most shops use barcode scanners for a number of very good reasons. Input and output is a very important consideration to make when designing a new system.