My headphone insulation is looking pretty rough and is getting progressively worse.
Just from my understanding of electronics I'm guessing the fine metal wire with the green stuff on it is some kind of shielding, as well as the foil, and it's the coloured wires underneath that is important. Is that right? What is the white one alongside the coloured wires that looks like it's made up of some kind of fibre?

How should I go about repairing it?