Meaning of the word "what's up" in English

What does "what's up" mean in English? Explore the meaning, pronunciation, and specific usage of this word with Lingoland.

what's up

US /wʌts ʌp/
UK /wɒts ʌp/

Exclamation

a casual greeting, often used to ask 'How are you?' or 'What's new?'

Example:
Hey, John, what's up?
I saw him yesterday and said, 'What's up?'