What are the functions of non-verbal communication?

There are following six functions of non-verbal communication.

(1)   To provide information either consciously or unconsciously.

(2)   To regulate the flow of conversation.

(3)   To express emotion

(4)   To qualify, complement, contradict or expand verbal message.

(5)   To control or influence others.

(6)   To facilitates specific tasks, such as teaching a person.