A family unit is a social group of two or more people, related by blood, marriage, or adoption, who usually live together in the same household and often share economic resources and responsibilities. This is a fundamental social institution in most societies, providing a context for socialisation, emotional support, and the care of its members, particularly children. The structure of the family unit can vary across cultures and over time, with the nuclear family (a couple and their dependent children) being the most common form in many Western industrialised societies, while extended families (including other relatives like grandparents, aunts, and uncles) are more prevalent in other parts of the world. The family unit plays a crucial role in the transmission of cultural norms and values from one generation to the next.