I partly agree with Tom Bliss's 27 Feb 10 - 01:37 PM posting, but (as in my previous posting) I don't think the dividing line is at all as sharp as he suggests. Yes, sound recordings stabilise words and tunes, but that doesn't eliminate all changes, and some singers deliberately make major changes to traditional songs. We can approve or disapprove of such changes according to our personal tastes, but we shouldn't pretend they don't happen.

And, long before sound recording started, at least the words of many songs, though generally not the tunes, were stabilised by the broadsides.

Richard