Child development psychology typically outlines stages of development based on various aspects of growth and behavior. While there are different models and theories, one of the most well-known is Jean Piaget’s theory of cognitive development. Here are Piaget’s stages:

1. Sensorimotor Stage (Birth to 2 years): Infants learn about the world through their senses and actions. They develop object permanence and begin to understand that objects continue to exist even when they are out of sight.
2. Preoperational Stage (2 to 7 years): Children become more adept at using symbols to represent objects and events. They engage in pretend play and develop language skills. However, they struggle with logic and often exhibit egocentrism, where they have difficulty seeing things from another person’s perspective.
3. Concrete Operational Stage (7 to 11 years): Children begin to think logically about concrete events and objects. They understand conservation (the principle that quantity remains the same even when the shape changes) and can perform basic mathematical operations. However, abstract thinking is still challenging.
4. Formal Operational Stage (12 years and older): Adolescents and adults develop the ability to think abstractly and reason hypothetically. They can engage in deductive reasoning and think about multiple possibilities and outcomes.

These stages focus primarily on cognitive development. Other psychologists have outlined stages focusing on different aspects of development, such as emotional, social, and moral development. Erik Erikson, for example, proposed a theory of psychosocial development, which includes stages such as Trust vs. Mistrust, Autonomy vs. Shame and Doubt, Initiative vs. Guilt, Industry vs. Inferiority, Identity vs. Role Confusion, Intimacy vs. Isolation, Generativity vs. Stagnation, and Integrity vs. Despair. Each stage represents a conflict that the individual must resolve to progress successfully through development.