Constant throwing of insults, a rampant pandemic of personal attacks, the constant insistence in being right despite having no ground to stand on and referring to anybody who disagrees as an idiot. That kind of fun stuff. Being angry is fine, it happens. But past age 16 you're supposed to have figured out how to manage that in a way that doesn't affect other people, and it's not like we excuse it in people younger than that anyways. You could always say that "it's just people on the internet, don't let it get to you," and that would be my personal advice to anybody who is having issues with it, but you also can't account for what the person on the other side of the screen is going through. The standard should be compassion, empathy, kindness, respect, and none of those things are present in the majority of posts on these forums.