Desire

Freud repressed memories find they're way to the subconscious. This can lead to many mental diseases. The only way tu cure it is to deal with the repressed memories.
Freud communicated the human psychic as a diagram, at the top there is the conscious (tip if the iceber), then theres the pre conscious, and finally in the bottom is unconscious. And throught there's is the ego and super ego.
Case study of Freud- Little Hans.
Little Hans had fear of horses. Freud deduced that the root of his fear comes from the Oedipus complex, so the infant boy find inappropriate feelings for his mother and he feared that his father might castrate him, so his father becomes a rival for the attention of the mother. Symbolicly his father is represented by the horse. Because the horse were the integral part of society, and being bit by a horse meant being castrated. So in a nutshell the unconscious manifested to a fear.
Vance Packard talks about desire in his book "The Hidden Persuaders". In once chapter he discusses how shell shocked soldiers after the world war II had a craving for milk, and this tranlated as they're unconscious craving to go back to child hood and become dependant on the parent figure. And marketing took tgat idea of desire and applied it to selling products.
Jacques Lacan talkes about how unconscious is structured like a language, semiotic. By that he meant that the language speak us, language thinks us. It allows change and distortion in our representation.'desire is neither the appetite for satisfaction, nor the demand for love, but the difference that results from subtraction of the first from the second'. Desire itself is built upon the lack of other needs. As animals we have biological needs, but as humans we have emotional needs. They're two different things but they're still bound together. But the problem is that although our physical needs can be stisfied, our emotional ones can't. And desire is used to differentiate between the two.