In order to record music onto a computer, it would be useful to be able to make music in the first place. You can get data into a computer in a variety of ways, but because we're talking about music, let's examine how you would use a musical instrument as an input device, even if that is a funny name to describe an eighteenth-century Stradivarius. A computer doesn't judge your musical talents or tastes, or the aesthetic quality of an audio signal.