Residential property refers to real estate used primarily for housing—where people live. This includes single-family detached homes, semi-detached houses, townhouses, condominiums, and apartment buildings. For property tax purposes, residential property typically forms its own class, usually taxed at lower rates than commercial or industrial property. Residential properties are assessed based on what similar homes sell for in the area. Different residential sub-classes may exist, such as multi-residential (large apartment buildings) sometimes taxed at higher rates than single-family homes. Residential property represents the largest category by number of properties in most municipalities and generates significant property tax revenue.