Are puns the same as one-liners?
Puns are a play-on-words, and one-liners can be sarcastic.
You cat to be kitten me right meow.
^ That is an example of a pun, as the sentence plays on the fact that "cat" sounds like "got," "kitten" sounds like "kidding," and "meow" sounds like "now."
One-liners can be "comebacks," puns, or sarcastic remarks.
Examples could be "yo mama" jokes or something like that. They aren't necessarily the same thing, but they can be.