How to Develop a Driver for an MP3 Player?

i built this board for the class. I stride from another board to the ta one, which another faculty member had made before. So actualy, like designed that board. Like everything about this board, iis desir tento take off from bi. E gtting blurred, right? Not got a watch on the tube. Ok. Now, i 'm curious too, when you say they make an mp three player, like, what is the end result of this? Like, how much of the hardware, soft board did they actually, like, assemble, or whatever?