Comma before proper nouns.

[Matthew McKinney]

In the sentence, "Whats going on, Matthew?" Is a comma really needed before the proper noun? If so why?

 

[5jj]

Welcome to the forum, Matthew. :hi:

We separate the name of a person addressed from the rest of a sentence by a comma,

 

[Barb_D]

There is a lot of difference between:
I hate to ask Matthew.
and
I hate to ask, Matthew.

 

[Rover_KE]

Note that you need an apostrophe in "What's going on?"

Rover