a song that has evolved through the oral process
a traditional song handed down by oral tradition
songs which are created and perpetuated within folk groups to serve such purposes as celebration, entertainment, protest and belief.
a song of unknown authorship passed orally from generation to generation. A folk song usually deals with things of daily life; it is often heard with slightly changed melody or words. Accompaniments may be added to folk songs, but they are not an integral part as are the accompaniments of the art song.