In every field of engineering, calculations are essential. Sometimes these calculations are simple, and performed using a notepad and engineering calculator or, more likely, a spreadsheet program like Excel. But, engineering calculations, much like life, are not always simple. Calculations have to take into account more than just the technical aspects of the task in hand and also consider other aspects such as efficiency and cost. Lets take, for example, the complex calculations needed to design an electric motor or transformer. You need to consider the type of lamination iron to be used, the size of the core, type of insulation, and chose between aluminium or copper conductors. During the calculation process, you have to tie all these elements together to optimise the design, taking into account efficiency, cooling, and cost.