Since man is communicating in many different ways, even small movements of the hands, arms or wiggle facial muscle contractions are perceived by the recipient, who does not respond.
In interpersonal relations very often need a personal conversation in private. Then the observation of facial expressions partner and his body control is very useful. Even if the recipient is not aware of any rules governing the body language, unconsciously sends and receives signals affirmative or negative words.
The simplest movements of the facial muscles express their feelings clear and simple – to raise eyebrows is a surprise, think wrinkle forehead or expresses disagreement on the solution, flat and wide smile, showing his teeth at the same time can be a symbol of mockery, and squinting eyes behind suspicious.