Adolescence occurs between puberty and legal adulthood, typically between ages 12-19. It involves physical, psychological, and social changes. Physically, adolescents experience puberty and rapid growth. Psychologically, they develop a separate identity from parents and form new relationships. Their cognitive abilities also advance to think more abstractly. Socially, peer relationships become important and they gain independence from family. This stage presents both opportunities and hazards as adolescents adjust to these significant developmental changes.