1) A casual greeting used by an individual or group or individuals addressing an other individual (or group or individuals). Often used instead of or in conjunction with (following) word such as hello, hi or hey
It should be noted that this phrase is not only used in by english speakers of all nationalities and dialects but by speakers of many different languages across the globe
see
que pasa and
ca va
2) A question used to inquire about the status of an on-going process or event. In this interogative state the sentence carries a question mark.
see also:
when the going gets good,
1) dude: "hey how's it going bro!"
bro: "not bad dude, I havent seen you
for time..."
2) dude: "
s'up man, I heard you had some problems with your girl. how's it going? things getting better?"
man: "
get bent..." *cries into his beer*