A type of blues usually played on non-electric musical instruments. It embraces a wide range of guitar and musical styles that thrived in the early days of the music style's gestation.
But folk blues is not limited to merely guitar music, but is an elastic enough term to also include down-home or 'roots' music played on mandolin, banjo, harmonica and other non-electric instruments. Folk-blues evokes the sound and image of a rough-hewn, somewhat informal music, a sound and style born of southern plantations, house frolics and juke joints.
The term overlaps significantly with the more general country blues, but is a more useful category for music which does not easily fall into any one of the various regional blues styles and variations.