Same here Lottie, todays American humour isn't particularly my scene either, but I found the explanations interesting in that link.
Having said that, we love the likes of WC Fields, Laurel & Hardy, Buster Keaton, etc. Not forgetting our own Charlie Chaplin.....
Funny you should mention Tommy Cooper, only we saw him 'off duty' once in a London pub & he looked such a misery guts, bless him! lol
He was very funny on stage though, along with lots of the other 'oldies', sadly no longer with us!