The ego, which is the part of the personality that provides a buffer between the id and the outside world.
Ego means the 'I', the conscious awareness of oneself (one's self). According to Freud the ego is that part of the personality closest to external reality which holds the ring between the unconscious drives of the pleasure seeking ID on the one hand and the internalized restrictions of the superego on the other. Neurosis in Freud's view is thus the result of the ego being unable to maintain harmonious relations with the id and superego because the power of their unconscious drives is too much for it to cope with.