Yes, it's mostly used as a greeting and conversation starter and not really meant to be answered, especially if it is used first. Meet up with a friend and he/she says, "Hey, what's up?" you could say anything like, "Nothing much." or just jump right into a conversation. Most of the time I just into a conversation.
I see it as "How have you been doing?" so I normally answer, "I'm doing fine" then I ask them back like "How are you? or How's life?" lol I never ignore it unless I don't feel like talking with the person.
I usually don't even reply since I find it so annoying. From what I can remember, most conversations I've had that have started out with something like that died off pretty quickly and weren't really conversations at all
lmao the only people who message me that are strangers so i usually ignore it or just say "yo". none of my friends just say "sssup" lmao but if they ask what i'm up to i'll tell them??
Depends on what I am up to, I'll sometimes do a vague description of what I am doing, usually just one of two words since they couldn't offer me more, and then ask "you?" So if someone asked me now I'd be like "Working, you?"
if u go into Real Depth of what youre doing and write a lot theyll be like -_- and leave ive noticed lmao that's fun to do when annoying boys try to message u