Something as undemanding as a smile can show openness in one ethnicity, impatience in another, and embarrassment in a third. Even silence has a different meaning in different places. Language learners will basically put loads of their money and time into mastering the structure and vocabulary of an overseas language without ever thinking about non-linguistic parts or gestures of communication. If you are planning to go to the overseas then you are suggested to know the meaning of different gestures of your destination to avoid making an awkward faux pas. Do some careful research on finding gestures that have different meaning in different country.