Person might doesn't know everything about itself and others. Like there might be things that person doesn't know but the others know by itself, there might be things that the person knows but the others doesn't.

Johari Window that composed with four perspective, is the model that developed in 1955 by Joseph Luft and Harry Ingram. It is about the how much people want to representing, explaining,telling theirselves to others.It is composed by intersection of two dimentions that What person know by itself and what others know about himself/herself. According to johari windowsi this spots can be changed. Blind spot getting smaller when people start to learn theirselves by the others thoughts and open spots are getting larger. Any changes occurred for a spot, effects other spots.