This document discusses several theories of human development, including psychoanalytic theory, behaviorism, cognitive theory, sociocultural theory, and epigenetic theory. It addresses key concepts within each theory such as Freud's psychosexual stages, Bandura's social learning theory, Piaget's stages of cognitive development, Vygotsky's zone of proximal development, and the interaction between genes and the environment. The document also examines debates around the nature vs nurture controversy and how different theoretical perspectives approach conditions like ADHD and homosexuality.