Legal adulthood--Age of majority

Legally, adulthood means that one can engage in a contract. The same or a different minimum age may be applicable to, for example, parents losing parenting rights and duties regarding the person concerned, parents losing financial responsibility, marriage, voting, having a job, serving in the military, buying/possessing firearms (if legal at all), driving, traveling abroad, involvement with alcoholic beverages (if legal at all), smoking, sexual activity, gambling (both lottery and casino) being a prostitute or a client of a prostitute (if legal at all), being a model or actor in pornography, running for President etc. Admission of a young person to a place may be restricted because of danger for that person, concern that the place may lead the person to immoral behavior, and/or because of the risk that the young person causes damage (for example, at an exhibition of fragile items).

One can distinguish the legality of acts of a young person, and of enabling a young person to carry out that act, by selling, renting out, showing, permitting entrance, participating, etc. There may be distinction between commercially and socially enabling. Sometimes there is the requirement of supervision by a legal guardian, or just by an adult. Sometimes there is no requirement, but just a recommendation.

With regard to pornography one can distinguish:

being allowed inside an adult establishment
being allowed to purchase pornography
being allowed to possess pornography
another person being allowed to sell, rent out, or show the young person pornography, see disseminating pornography to a minor
being a pornographic actor: rules for the young person, and for other people, regarding production, possession, etc. (see child pornography)
With regard to films with violence, etc.:

another person being allowed to sell, rent out, or show the young person a film, a cinema being allowed to let a young person (under 18) enter
The legal definition of entering adulthood usually varies between ages 16–21, depending on the region in question. Some cultures in Africa define adult at age 13.

According to Jewish tradition, adulthood is reached at age 13 (the minimal age of the Bar Mitzvah or Bat Mitzvah) for Jewish boys and girls; they are expected to demonstrate preparation for adulthood by learning the Torah and other Jewish practices. The Christian Bible and Jewish scripture has no age requirement for adulthood or marrying, which includes engaging in sexual activity. The 1983 Code of Canon Law states, "A man before he has completed his sixteenth year of age, and likewise a woman before she has completed her fourteenth year of age, cannot enter a valid marriage".[6] According to The Disappearance of Childhood by Neil Postman, the Christian Church of the Middle Ages considered the age of accountability, when a person could be tried and even executed as an adult, to be age 7.

In most of the world, including most of the United States, parts of the United Kingdom (England, Northern Ireland, Wales), India and China, the legal adult age is 18 (historically 21) for most purposes, with some notable exceptions:

1.Scotland (United Kingdom) and the Netherlands (16)
2.British Columbia, New Brunswick, Newfoundland and Labrador, Northwest Territories, Nova Scotia, Nunavut, Yukon Territory in Canada; Nebraska and Alabama in The United States, and South Korea (19)
3.Indonesia and Japan (20)