Traditional folk:-
1. Like a scene from a Thomas Hardy novel. Country people in a village pub, accompanied by fiddle, concertina or whatever instruments the village Waits had managed to scrounge.
2. Like a post-war Junior School. Teacher on piano thumping out the chords, fifty kids in a classroom singing "The Drummer and the Cook" from a BBC schools songbook.
3. Like Peter Pears at The Maltings, or Kathleen Ferrier. Highly refined and bowdlerised versions of slightly suggestive songs sung and played by classically trained musicians.
4. Like a fifties Folk Group. Four university graduates with guitars and/or banjos, dressed as fishermen, singing folksongs, mainly from America.
5. Like Bob Dylan and/or Joan Baez. Solo performer with guitar singing mostly recently composed songs, often with a strong political or social message, and a transatlantic accent.
6. Like the New traditionalists. Solo performer or duo, guitar played in open tunings and with a very percussive style, fiddle player optional. English songs verified by visits to C.S. house, sung in a rural English accent (or equivalent from the other nations and regions of the UK.)
There are so many traditions, even in one small country, that either everyone is traditional or, nobody is. How many times does something have to be repeated before it becomes a tradition?

Cheers
Dave