Urban- a surrounding a city

Suburbs- mixed residential area with city and separate community but within communication distance.

Rural- open lands with few homes

Settlement- a place with a permanent human population 

Percent urban- an indicator of the proportions of the population that lives in cities and towns as compared to those that live in rural areas. 

Suburbanization - process of people moving, usually from cities, to residential area on the outskirts

Urbanization - ongoing process that does not end once a city is formed  

Reurbanization- some suburbanites return to live in the city

Exurbanization- when others move farther out into rural areas and work remotely

Satellite city- when an established town near a very large city grows into a city independent of the larger one

City-states- the most successful of these settlements

Urban hearths- areas generally associated with river valleys in which seasonal floods and fertile soils aided the production of an agricultural surplus

Metropolitan/ Metro area: A large collection of cities across in which which population density is high and continuous.

Metropolitan statistical area (MSA): Another way to define a city. At least 50,000 people, the country in which it is located, and adjacent counties that have a high degree of social and economic integration or connection with the urban core.

Micropolitan statistical areas: A way to describe a smaller city. At least 10,000 people (less than 50,000) , The country in which it is located , and surrounding counties with a high degree of integration. 

Nodal region: A focal point in a matrix of connections