Face Perception refers to the skill of reading other people's emotions through their facial expressions. The human face, through an immense number of combinations of nerve and muscle movements, is capable of expressing a vast spectrum of information to others.
You may remember that, when you were growing up, learning to use the facial expressions of parents, teachers and other adults as a means of gauging approval and safety. As we grow older, we learned about more subtle expressions such as annoyance, irritation, headaches, etc. Additionally, it is now medically known that some facial expressions can be signs of physical problems that can be recognized by trained practitioners.