What is the definition of a rural area?

National Geographic defines a rural area as an open swath of land that has few homes or other buildings and not very many people. Population density of rural areas is very low, and the primary industry in most rural areas is agriculture.

The U.S. Census Bureau defines two types of urban areas: Urbanized Areas of 50,000 or more people and Urban Clusters of at least 2,500 and less than 50,000 people. Rural areas are defined by the Census Bureau as any areas that fall outside of the aforementioned urban areas. Rural areas are sparsely populated, as the vast majority of people live in urban areas.