There were many theories which were published in books or lectures that he taught, which were highly controversial. Among them The Theory of Unconscious, is actually very popular nowadays; present functional brain imaging and EEG support for the claim that consciousness is just an tip of the iceberg. According to the theory, mind is divided into three levels, one the conscious, penultimately the pre conscious which is very much close to both conscious and unconscious hence assessable by both where even the memory resides and finally the unconscious, where the "Id" resides, about which i will explain soon. Well now this is also where i need to tell you one more concept, as the three tiers of consciousness is displayed, the areas of brain and its processes is necessary, from bellow up where the Id stays, that is unconscious site where the primitive instincts before the evolution dwells, this has delayed action that is its effects kicks in a bit later stages and has discounting effects over all inhibitions, the pre conscious state of the frontotemporal area where the subconscious plays an important role so as to release the inhibitions over both conscious an unconscious instincts, and of course the conscious section maintained my pre frontal cortex and among all its known functions it also has impulse control aspect. And according to this theory the fascinating thing is that the largest part of the mind is the unconscious and rest of the two are very minute, lesser than 1/3rd as a whole extant, its like a planet at an edge of a cornered galaxy.
So, earlier i was talking about "Id". The “id” translates the organism's needs into instincts or drives that also are called as wishes. It is special in that it acts to survive and reproduce, and it is guided toward those goals by its needs – hunger, thirst, pain avoidance, and sex. At birth, the human nervous system is little more than that of any other animal, but its important to make a note that it is essentially pure "Id". Unfortunately with age needs get stronger, and wishes increase. As i was mentioning above, the small portion of the mind, the conscious, is hooked to the world through the senses. Around this little bit of consciousness, during the first year of a child's life, some of the "Id" becomes “I” or ego. The ego relates the organism to reality through its consciousness, and it searches for objects to satisfy the wishes that "Id" creates to represent the organisms needs. The ego, unlike the "Id", functions according to the reality principle, which says "take care of a need as soon as an appropriate object is found." It represents reality and, to a considerable extent, reason.
Alright, after learning about the concepts of Id and its conversion into I, you also need to know about "Superego". This is based on the life and the encounters of a child with age. When the being occasionally meets with objects that assist in attaining the goals or encounters obstacles in the world, the being now keeps a record of these obstacles and aides. In particular, it records rewards and punishments presented by the mother and father, two of the most influential objects in a child’s world. This record of things helps to avoid or strategies are made to become the "Superego". It isn’t complete until about age seven, and in some people, it is never completed. There are two aspects to the "superego". One is the conscience, which is an internalization of punishments and warnings, and, and the other is called the ego ideal, which evolves from rewards and positive role models. The conscience and ego ideal communicate their requirements to the ego with feelings like pride, shame, and guilt.
So, in childhood, a new set of needs and wishes that derive from social origins arises. However, these wishes often conflict with those from the "Id". The superego represents society, and society may want you to never satisfy your needs.