Give some examples you have seen of peoples’? abnormal? behavior. After you describe the instance, writ

Give some examples you have seen of peoples'  “abnormal” behavior. After you describe the instance, write down why this is “abnormal”. In other words, what is your definition of abnormal? 

Example: When I was in college- and this was roughly a hundred years ago, before mobile phones- there was a man that used to walk around town talking to himself, with gestures, like he was having a lively conversation with someone. He'd even stop occasionally and really lean in, reinforcing some point he was making, like he was talking to someone else..only nobody was there but him!

Several years later, bluetooth technology came out- and I know that's stilll an old reference, some of you may not remember seeing- but suddenly, everyone was this guy, walking around with a bluetooth earpiece in, having a lively conversation as if in person, complete with hand gestures and body language! 

So, what defines abnormal behavior? is it objective, or is it in the eye of the beholder, so to speak? Are there cultural, socioeconomic or gender elements to it? Does it change with times?