Personality psychology is a branch of psychology that studies personality and individual differences. Its areas of focus include:

• Constructing a coherent picture of a person and his or her major psychological processes ^[1]
  
• Investigating individual differences, that is, how people can differ from one another.
  
• Investigating human nature, that is, how all people's behaviour is similar.

Personality can be defined as a dynamic and organized set of characteristics possessed by a person that influence everything they do in situations.

PERSONALITY: identifies the person, it has a past in the history of psychology with theoretic traditions.

The personality for me is someting that we learned this i can see because of the experiment of my dear friend John B Watson with behaviorism, he tried to proove that we were not born with fears we learn them, so i can conclude that our personality is simething we learn due to our surroundings.

http://psychology.about.com/od/overviewofpersonality/a/persondef.htm