What's up?

informal question

Definition

1: Used to greet someone; used to ask how someone is doing; used to ask someone what the problem is

Examples

A and B are co-workers and are passing each other in the hallway.

A: Hi, what's up?!

B: What's up.

C and D are friends who see each other in the supermarket.

C: Hey, what's up?

D: Oh not much. I'm still working at the bank.

E enters the room and asks his co-workers.

E: What's up - why does everyone look so serious?

Co-worker: The boss says someone will get fired today.

Responses to What's up? can include:

Not much.

Nothing much.

Nothing.

Nothing new.

Well, I got a new job! (or other news you have)