What is the difference between urban areas and suburbia?

The main factors to consider are population density and buildings. Urban areas tend to have high-rise buildings and public transportation. People live in perhaps 30 square feet per person, with barely a tree anywhere. In suburban areas, we tend to see buildings with mostly two stories and people drive in cars to go anywhere. People live in perhaps 1000 square feet per person; the house has a lawn and trees are everywhere.

Rural Urban Suburban are also general designations given by the US government agencies (often used for determining grants and tax incentives). Not all agencies use the exact same population break downs or terms (exam. some may use Metropolitan Areas). Furthermore, agencies who use Rural, Urban, and Suburban data, sometimes define the boundaries different than other agencies.

Example:

Urban: 3,000+ persons per square mile

Suburban: 1,000 ‐ 3,000 persons per square mile

Rural: less than 1,000 persons per square mile