Body language, proximity - how close we comfortably stand to others, how loud we speak, and how long we wait before we interrupt others are all things that our culture can imprint on us.
The one that rings the loudest bell for me is, personal space. I found that my personal space was often invaded while teaching English and living abroad in Asia, especially while in Korea and secondly in China. And it was a bit annoying at times.
Why did I feel that way? Well, it could have been because of the fact that I was an American, we love our space, right? Or it could have been because I grew up in the country side, with fields of space. Or maybe it was because I spent too long of a time teaching English abroad, nearly four years straight. Or better yet was it because of the ultra large urban populations (3-19 million people) that I was living among? I don't know, but one thing is for sure and that was that I was often annoyed because my space was being infringed upon. Welcome to urban Asia.
So how did they invade my space? Well, a daily experience walking through the subway station or down a busy street for that matter could be a rather abrasive experience. Some will greet you with an elbow or maybe bump shoulders without much of a second glance. And before you know it you may find yourself armed and ready to return those elbows and shoulders as you make your way through the crowds.
The other way of space invasion came in the way of my personal encounters. This could happen on the street as well, or at the market, or perhaps even at work with a colleague.
Let me introduce to you the "intimate stranger". Someone who you know or don't know that's curious about you, the foreigner, and suddenly steps into your space for an "intimate" conversation. It could be just the usual small talk, like "Where are you from?", "Why are you here?" or the "Why aren't you married?" question, but it's intimate and in other words closer than you're comfortable with.
I estimate that it's probably perfectly normal for them to stand this near and chat, but it's rather unusual for you the westerner.
Your bubble will likely be popped from time to time, while living abroad in Asia, as their concept of personal space is different. It's a lot smaller.