Becoming an adult has legal, biological, psychological, and social dimensions that vary globally. Legally, adulthood is defined by reaching the age of majority, which is most often 18 but varies by jurisdiction, granting full legal rights and responsibilities. Psychologically and socially, it involves a gradual process of taking on more responsibility, making independent decisions, developing a stable identity, and learning to manage lifes challenges, which can continue into ones twenties and beyond.