Dialogue is one thing. A dialogue is another. That's right, Shmoopers, that teeny-tiny little article changes it from an exchange of words to an entire work of literature. And if you want to take it one step further, the dialogue usually refers to an entire genre. Italics for emphasis and to make us feel a little Frenchier.
The dialogue genre makes use of—wait for it—dialogue. Yep, it's usually somewhere between two and a handful of people chatting away about some super-esoteric topic.
Back in the day, authors would use real, live historical figures to speak their words for them, too. Can you imagine if David Sedaris put words in the mouth of Barack Obama and George W. Bush? The blogosphere would go nuts, which brings us to the fact that yeah, dialogues could be a wee bit controversial.