Chord Detector is a mp3/wav music player with real time chord recognition.
There are geniuses that can determine a chord in a snap just by natural talent - via ear training, then there are the techie people that will use tools to get the same effect - via chord detection software like Chord Detector.
Just load the song that you want to learn the chords from, press play then the chords will be displayed in real time. The technology behind Chord Detector is described as a program that watches a set of virtual strings vibrate in response to real-time audio frequencies, then it makes chord suggestions based on the vibrations.
This is designed to help musicians easily learn the chords of a song.