Most common gestures
An example for different interpretation is the gesture which indicates: "follow me." Whereas in some countries, like Germany or the UK, the hand is outstretched, palm open, fingers pointing upward and a scooping motion is made toward the body, the same gesture is made in for instance, Spain and Turkey with the fingers pointing down. Using the "fingers upward" position would indicate a sexual interest.
Another gesture involving fingers is the formation of a circle with thumb and forefinger. Here the significance reaches from approval (that's fine, that's OK) in Europe to a downright insult (you are a pig) in Turkey.
Crossing your arms over your chest is another very common gesture. It can mean different things in different situations. In a friendly conversation, the gesture can indicate: "I'm at ease listening to you and interested in what you have to say." In a crowded place however, crossing the arms is often done involuntarily as a sign of erecting a barrier to avoid invasion of private and personal space.
Constant eye contact in a conversation can signal interest in what the other person has to say. However, it can also mean distrust in the following sense: "I don't trust you, I don't dare take my eyes off of you in case you cheat me."
All the above gestures are made voluntarily as well as involuntarily. They are also techniques used skilfully in interviews or interrogations.