Well using an array, is so much efficient.
Because it'll allow you to save so much time and energy especially if you were asked to finish a program at a short amount of time. It'll also allow you to create as little lines of codes as possible.
control unit this part controls the input and output devices.
arithmetic logic unit this is the part that does all the working out: it does all the maths and makes the decisions.
immediate access store this is the memory available for programmes and data.
mail merging is use in multi if you have a single email but you need to send it to many recipients this thing is useful because you are merging many recipients in a single