Household economics studies the way households, families, or individuals manage resources such as money, time, work, and assets. A household is defined as a group of people, related or unrelated, living in the same dwelling and includes roommates, families, and extended families. Much of the theory in this field is used to explain changes in household behavior over time. It is a diverse field of inquiry studying consumer decision-making for households. For example, trends in savings and consumption, investment in higher education, changes in the workforce, and changes in the formation of the family all affect lifespan-related decisions for families and households. This entry summarizes key points in understanding economic decisions affecting households over the lifespan.