People in lower grades who just curse. Stop trying to act adult, stop spitting out random words like its vile!
People who just say "xD" all the time. It's not funny children, just terrible. Again, it is NOT FUNNY.
People who have no respect for people actually going through depression and are suicidal. They go "I go through tougher stuff, shut up." Why don't you? They actually have it, and you're making a mockery out of it.