The typical age of attaining legal adulthood is 18, although this may vary by legal rights and country.
Human adulthood includes psychological adult development. Definitions of adulthood are often inconsistent and contradictory; a person may be biologically an adult, and have adult behavior but still be treated as a child if they are under the legal age of majority, though one may legally be an adult but possess none of the maturity and responsibility that may define an adult character.
In different cultures there are events that relate passing from being a child to becoming an adult or coming of age. This often requires the passing a series of tests to demonstrate that a person is prepared for adulthood, or reaching a specified age.
Most modern societies determine legal adulthood based on reaching a legally specified age without requiring a demonstration of physical maturity or preparation for adulthood.
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Celebration of Confirmation, (Western Christianity) coming of age celebration
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