I know many people have already posted about non-verbal communication and body language and stuff like that. But here I would like to touch on a point I believe many people overlook in day-to-day communication and in the forming of relationships. (Chp. 6 huh, Mr. Murali?) Haha, what is this point? It's very very simple, actions. The actions that you do for a friend or your family has a hugely positive or negative impact on how others view you. As human beings, with listening being difficult and all, we tend to remember the actions of others towards us rather then the things they said to us. Action is associated with words. A young child who throws tantrums becomes quiet when he sees the cane, although he might not give any reaction if just being scolded. This is because he has connected the cane to discipline.
Another example, your parents buying you an unexpected gift. They may have said something along the lines of I love you or stuff like that but what really showed the love? The action of buying the gift. Which also brings me to another aspect, that action reinforces words.
Thirdly, doing something for somebody else not only makes them feel good but you as well. As the saying goes: Do unto others what you want them to do unto you. [1] This is also true to fact that two ways of letting somebody else know you care are by acts of service and gifts. [2] Acts of service being defined as doing something for others for which you get no gain. I don't think I need to define gifts. :P
Haha, so that's it I guess, part and parcel of non-verbal communication. If you don't believe me, try it, do something nice for somebody who doesn't expect it at all and see what it communicates to them. =] Peace out.
References:
[1] Matthew 7:12
[2] Northfield Publishing, Chicago, Chapman. G, The Five Love Languages, 2000.