Well I know that now after checking various wiki links and it certainly turned up some interesting cow milking videos. Shame I'm on soya milk these days. Not sure how you milk a soya or where they live.
Condenser microphones work by sound vibrations pushing one half of a wobbly bit that alters the distance between another wobbly bit and changes the capacitance, this is then fed out as an electrical signal.
Unlike a dynamic microphone which has sound vibration moving a wobbly bit in and out of a magnet and some wires creating an electrical signal in the same way a generator does. They're generally more sensitive than dynamic microphones but are more prone to feedback.