Households most often perform five kinds of activity: producing goods and food, distributing them among members, passing property and rights to the next generation, raising children, and living together. These tasks can be bundled into one group or split across several, so a household is best mapped by which of the five it handles.
The household sits between the individual and the wider society, translating large forces into everyday decisions about who gets what. Inside it, members both cooperate and bargain over resources and responsibilities, so it is never simply a harmonious unit.
Rather than defining a household by its shape (who lives under one roof, how they are related), ask which group actually carries out the basic work of daily life. The authors shift the question away from structure toward activity, because the same tasks get done by differently shaped groups in different places.