An interesting fact is revealed by MIT's Fake Smile Detecting software. 

The fact is: 


90 percent of people smiled when they got frustrated. And even more interesting is that, half of the times, the person witness to this smile spots the frustration or Fakeness.


Thus if you are offended or feel uneasy by a friend's/colleague's comment or behaviour, and smile, half of the times he/she knows the smile on your face is frustrated.


So in order to stop giving any clues to the person in front, DON'T SMILE AT ALL.

----