There are many theories on how a human develops. Most babies follow a certain pattern of development but the controversy is which person's developmental pattern of development is correct? Erik Erickson, Sigmund Freud and Jean Piaget's developmental theories are similar. Each of the theories goes through a human's development chronologically, giving a guideline of when certain developments happen. For example when a child is supposed to walk or when a child is going to speak. It is only a guideline and these theories are not supposed to be held too strictly.
Sigmund Freud's developmental theory was his psychosexual stages of development. His stages were: the oral, the anal, the phallic, the latent and the genital. The oral stage focused on the mouth. It is the reason why all babies like to put everything in their mouth. It is how they explore the world. This stage is usually from ages 0-1.
Not completing this stage means that the person will be orally fixated all their life. They might pick up such bad habits as smoking. The anal stage is focused on the anus of the child. During this stage the baby is trying to conquer such tasks as toilet training. The consequence of not completing this stage is a person being "Anal Retentive." This stage lasts from 1-3 years old. The phallic stage is by far the most controversial stage of Freud's developmental stages. This stage states that a child wants the parent of the opposite sex and wants to kill the other parent. This is called the Oedipus complex. If you do not complete this stage then you can become sexually deviant. This stage lasts form ages 3-6 years old. The latent stage of development means that you want to identify with same sex peers. At this...