How does body language relate to me?

After learning this chapter, I am surprised at the different body languages have different meanings in different cultures, even smiling. I think there are some body languages came from human nature, which is not distinguished by the cultures, liked baby crying means they are hungry and unhappy, when they smile, it means they are happy and  comfortable. Some body languages were influenced and learnt; for example, when I met my friends, we would hug and smiled; In France, they hugged and kissed the faces; I think these greeting body languages depends on the degree of intimacy and friendship with the others. Some body languages were shown unconsciously, sometimes I would express my feelings through the body languages unconsciously, my friends would tell me; after that time, I sometimes would observe other’s body languages.