When your name is Tommy Wiseau and you are directing, starring in and filming your own movie called "The Room" and you have a friend called Mark, then the only expression you can use to greet that friend is "Oh hi Mark".

when you're hungover as shit after a spending a night drunk as a skunk

(exclamation) a greeting you say flatly to the person who has been watching you doing something embarrassing.

Oh hi mark

when you get caught smashing and youre embarassed so you say oh hi mark

Phrase used to greet your friend Mark used from a movie called Rooftop whose protagonist is Tomy Wiseau and its often used by Logan Paul on his daily vlogs.