What's up?

"What's up?" is considered almost rude. I would not use this phrase today.

"How is it going?" is not used. You would say: "How's it going?" This is would be used between two men who know each other. This is borderline rude. I would not recommend using this.

"What's going down?" can have prurient connotations. This would only be used between men in a rowdy situation. I you

Hi.

It is highly dependent on the working environment.

But I personally didn't like it when one of my new colleagues told me what's up? when we really didn't know each other very well.

I have the same impression about the other two.

Note, I have expressed my personal feeling. I didn't answer a language question.

I hope it helps

Hi,

What's up? How is it going? What's going down?

Tell me please, what's the difference? I understand all of them are informal? Yes.

But how much? Is it OK for 'What's up' between not very close colleagues, for example? Is
it for some age, maybe for youth mostly or not? Is it just a greeting or

Thank you very much, Anonymous and 'hrsanei'.

I exactly wanted to know a personal feeling.

Thanks