Density in urban planning refers to the intensity of development in an area, typically measured as the number of residential units per hectare or people per square kilometre. Low-density development features single-family homes on large lots; medium-density includes townhouses and low-rise apartments; high-density involves towers and intensively developed urban cores. Density significantly impacts municipal finances and services: higher density allows more efficient provision of transit, utilities, and services, while lower density increases per-capita infrastructure costs but offers more private space. Planning debates often centre on appropriate density for different areas, balancing neighbourhood character, housing affordability, transit viability, and growth management. Many Canadian cities are encouraging "gentle density" (townhouses, duplexes, small apartments) in traditionally low-density neighbourhoods to address housing shortages and meet climate goals.