Introduction This is an assignment to briefly explain four major developmental theories and to explain that how I am going to practically apply these four major theories in my real world teaching. The four theories are Psychosexual Development theory of Freud Sigmund, Psychosocial Development Theory of Erik Erikson, Cognitive Development theory of Jean Piaget and Moral Development theory of Lawrence Kohlberg. Erikson’s Theory of Psychosocial Development Introduction The German-born American psychologists described developments that occur throughout the lifespan. Erikson 's theory suggests that every human being passes through several distinct and qualitatively different stages in life, from birth to death. He is best-known for this theory and the concept of the identity crisis. The key idea in Erikson 's theory is that the individual faces a conflict at each stage, which may or may not be successfully resolved within that stage. For example, he called the first stage 'Trust vs Mistrust '. If the quality of care is good in infancy, the child learns to trust the world to meet her needs. If not, trust remains an unresolved issue throughout succeeding stages of development. So according to him all people go through a series of eight stages. At each stage, people face a crisis that needs to be successfully resolved in order to develop the psychological quality central to each stage. The stages I have selected from this theory to apply in my real world teaching is Industry