It might be easier to explain that sarcasm is sometimes delivered in a "snarky tone." It certainly
doesn't have to be... even Ben Stein could be sarcastic in his deadpan voice, but I'd say it may be more common than not
.
As for western humor... in my eyes, the difference between say... our humor and the UK's humor is that we make things
obvious. For example, I remember watching the movie Paul, which was written by Simon Pegg and Nick Frost (British citizens). There was a scene where Pegg's character tells the girl that she can use his bed and to ignore the tissues because he had a cold. Now, given the character is a major geek without a significant other, you probably have an idea what this
actually means.
In American humor, this would usually be represented by actually
seeing the tissues (the line in the movie took place outside the RV) and quite possibly the girl making a comment about them and so on. Just think of equivalent type of situations in movies like American Pie. Hmm maybe not the best example, but I think it gets the point across?
Another way to look at it is looking at stuff like Monty Python. The British humor there tends to be on the outrageous side. They have situations that you're supposed to laugh at simply because of how outlandish they are. I find that this humor tends to not be as funny the first time, but is usually fun afterward or when quoted. I do notice that there seem to be a lot more American comedies that take this approach of just presenting this odd situation that we're supposed to find amusing. This is unlike the other method of simply delivering funny lines. Kind of like when someone was showing me HBO GO the other day, they had Get Him to the Greek on, and one of the best lines came up...
PD: "You see that... I'm mind fucking you right now!"
JH: "Hehe I hope you're wearing a condom... because I have a dirty mind"
Well, I'm certainly no expert and all of this could be wrong!