If I can sing it, it's probably folk music, or well on its way. If I can play it on guitar, it's definitely folk music, 'cause I can't play anything more complicated (and damn those complicated folk tunes, anyway, like that #@%$&#*@ Night Herding Song, which I've now got two sets of chords for, neither of which works with the only tune I've heard, must be only cowboys allowed to sing it).