Most psychoanalytical theories share their emphasis on "the mind", the unconscious, its influence on behavior, and the continuity of individual differences- Sigmund Freud was the one to develop these core concepts. Sigmund Freud's psychoanalytical social behavior development theory (otherwise commonly referred to as his psychosexual theory) is the most controversial of all human development theories. According to Freud, human behavior is driven by the individual's need to satisfy their innate biological drives, and since the need to procreate is one of the highest on this list it was often his particular focus. Freud organized his description of the human's social behavior development into discontinuous stages by age.

Stage
Description
Oral
(0-1 year old)
An individual's main source of satisfaction in this stage is the oral activity of breast feeding so that pleasure association is transferred onto the mother and she becomes the child's first and most influencing love-object. Children who are taken off breast feeding too soon or are kept on it too long are subsequently said to become fixated in this stage building a habit of putting things in their mouth, e.g.- biting their pencils, pens, and or fingernails
Anal
(1- 3 years old)
An individual's main source of gratification comes from defecation. Children at this stage are very sensitive to their success or failure potty training, and if their needs are not meet they may become fixated in this stage often developing an obsessive and anal personality.
Phallic
(3-6 years old)
An individual's main source of pleasure derives from their genitalia. If their needs are not meet in this stage children may become fixated in their genitalia.
Latency (6-12 years old)
An individual's sexual energy is repressed in the unconscious and channeled into productive social activities.
Genital
(12 years old and up)
An individual reaches full sexual maturation and sexual intercourse becomes a major target for him. If the individual's needs are not meet the individual may become fixated on sex.

To better understand the above described stages of Freud's psychosexual development one might consider Freud's general concept of personality. Freud's structure of human's personality describes us ruled by our Id, Ego, and Superego. Since the ego does not emerge until after the first year of life, infants are ruled by their Id alone which unconsciously seeks pleasure and finds it in fulfilling his biological need of food (oral stage). Once the ego emerges after the first year of life, that is the more logical problem solving section of our personality, we go into the next stage (anal) and are cognitively ready to try and control our biological urges in order to fit society's expected norms, but because our biological need of defecation is still most present in the Id we subsequently find pleasure in fulfilling it. The Superego emerges somewhere in the beginning or end of the phallic stage after resolving the Oedipus complex (for boys) or Electra complex (for girls) which has us to repressing the sexual energy that has been ruling us and leads us into the latent stage of our psychosexual development. With puberty all of the sexual energy returns along with the continual struggle for balance between the Id, Ego, and Superego components of our personality.


*All information on this page was derived from source number 2 found on reference page.*


For more information on Freud and his theory consider these sites:

http://bjps.oxfordjournals.org/cgi/pdf_extract/VII/25/4

http://allpsych.com/personalitysynopsis/drives.html

http://www.youtube.com/watch?v=jfP9AIJA72E