The document defines a family as two or more related individuals living together. It discusses different types of families such as nuclear, extended, and blended families. It also outlines the family life cycle in five stages from bachelorhood to solitary survivor. Each stage is characterized by factors like the presence of children, income levels, and common expenditures. The document notes eight roles family members can play in decision making for products and services, from influencing to disposing. It also describes different types of family decisions like husband-dominated, wife-dominated, and joint decisions.