Folk music
Some singing was polyphonic, i.e. there were two or more parts (voices). Very often two voices would sing in parallel (going up and down together). In countries such as Russia persons sings in three or four parts, e.g. in the tradition of “podgolosnaya” (“underneath the voice”). In countries such as Britain this polyphonic tradition did not exist. Folk songs there were sung by one singer, unaccompanied.