Id is the original self, which refers to the original self, including the basic desires, impulses and vitality needed for survival. Id is the source of all psychological energy. It acts on the principle of happiness. It ignores social morality and external behavior norms. Its only requirement is to get happiness and avoid pain. Its goal is to seek individual comfort, survival and reproduction. It is unconscious and will not be perceived by individuals. Ego, which means "ego" in German, is the part where you can consciously think, feel, judge or remember. The role of the ego is to seek the satisfaction of the "id" impulse, while protecting the whole body from harm. It follows the principle of realism and serves itself. Superego is an ideal part of personality structure. It is formed by internalizing the moral norms and values of social and cultural environment in the process of individual growth. Its main function is to supervise, criticize and control its own behavior. It is characterized by the pursuit of perfection, so it is as unrealistic as the ID, and most of it is unconscious. It requires the ego to satisfy the ego in a socially acceptable way, and it follows the "moral principle".