1. Growth and development refers to the changes that occur during an individual's lifecycle from conception to death. It encompasses physical, cognitive, emotional, and social changes. 2. Studying growth and development allows one to understand typical behaviors and abilities at different ages, assess developmental norms, identify potential problems, and provide comprehensive care for children. 3. The main stages of growth and development are prenatal, infancy, early childhood, middle childhood, and late childhood/adolescence. Rapid physical and cognitive development occurs during infancy from birth to 12 months.