Body language
Body language is a language without spoken words and is called non verbal communication. We use body language all the time, for instance looking at someone means something different than not looking at someone.
It is important to note that body language has different meanings in different cultures. In the most European countries and America, for example people shake their head when they want to say no and nod when they mean yes, but there are cultures, for example in India or Greece, where they mean the opposite. Also some groups, such as gay people, people in slavery, prisoners, have developed a whole specific body language.
Body language is used especially to express feelings. For instance if we do not like someone, it is difficult to say that directly to the person. However, we can do it through body language and it would be quite easier. It is also difficult to lie or cover up our feelings through body language because then people always understand that something is wrong.
Several investigators estimate that at least 70% of the communication between people takes place through body language and tone of voice.
All these things once time again show what important body language is as a part of communication.
References: http://astore.amazon.co.uk/scientific-21/detail/0752858785
