And what are the different characteristics of these different forms of humour?
Having looked at the near duplicate question, it does raise some interesting material and supplies possible answers to the question. However it has also made it clear that this is a far more complex subject than I made it sound, and merits a far wider conversation than is possible on this site. The whole question of what we laugh at, and what defines humour needs to be considered.
But for anyone interested I recommend reading the duplicate question, and the responses thereto.