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- Understatement
a statement that is restrained in ironic contrast to what might have been said

Example: (page22)
Ford: No, its just that the world's going to end.

- Irony
A statement that, when taken in context, may actually mean the opposite of what is written literally; the use of words expressing something other ...

Example: (page 19)
Arthur: I eventually had to go down to the cellar
Prosser: That's the display department
Arthur: …with a torch?
Prosser: Ah, the lights had probably gone.
Arthur: So had the stairs

- Pun
a humorous play on words

- Sarcasm
witty language used to convey insults or scorn

Three other examples of something funny:

1. (page 19)
Prosser: Have you any idea how much damage that bulldozer would suffer if I just let it roll straight over you?
Arthur: How much?
Prosser: None at all!

2. (page20)
Ford: …Look, are you busy?
Arthur: Well, I've just got this bulldozer to lie in front of, otherwise no, not especially.

3. (page21)
Arthur: Six pints of bitter. And quickly please, the world's about to end.
Barman: Oh yes, sir? Nice weather for it. Going to watch the match this afternoon sir?