Density: Density refers to the number of individuals or objects per unit of area in a population. It helps measure how crowded or sparse an area is.
Urbanization: Urbanization is the process by which an increasing proportion of a country's population lives in urban areas rather than rural ones.
Megacity: A megacity is an exceptionally large urban agglomeration with more than 10 million inhabitants. These cities often experience unique challenges due to their size and complexity.