M.S. Rao's three levels of urbanization are a conceptual framework developed by M.S. Rao, an Indian sociologist, to understand the process of urbanization. This framework helps in analyzing and categorizing urban areas based on their level of development and characteristics. The three levels of urbanization are:

1. Level I: Primary Urbanization
Primary urbanization refers to the initial stage of urban development. In this level, urban areas are characterized by a small population, limited infrastructure, and basic amenities. The economy is primarily agrarian, with agriculture being the main source of livelihood for the majority of the population. Basic services like healthcare, education, and transportation are limited. The urban areas are often underdeveloped, lacking proper planning and governance. Examples of Level I urbanization can be found in rural towns and small villages that are slowly transforming into urban areas.

2. Level II: Secondary Urbanization
Secondary urbanization represents a higher level of urban development compared to Level I. In this stage, urban areas experience rapid growth in population, infrastructure, and services. Industrialization plays a significant role in the economy, leading to the emergence of manufacturing and service sectors. The urban areas are characterized by improved transportation networks, educational institutions, healthcare facilities, and other amenities. The government's role in planning and governance becomes more prominent. Examples of Level II urbanization include small and medium-sized cities experiencing significant growth due to industrialization and economic development.

3. Level III: Tertiary Urbanization
Tertiary urbanization represents the highest level of urban development. Urban areas at this level have a large population, advanced infrastructure, and a diverse range of economic activities. The economy is primarily service-oriented, with industries such as finance, technology, and tourism playing a crucial role. The urban areas are characterized by well-planned layouts, efficient transportation systems, high-quality educational institutions, healthcare facilities, and other amenities. Governance in Level III urban areas is more complex, involving multiple stakeholders. Examples of Level III urbanization can be found in major metropolitan cities like New York, Tokyo, and London.

Overall, M.S. Rao's three levels of urbanization provide a useful framework for understanding the different stages of urban development and the associated changes in infrastructure, economy, and governance. By analyzing urban areas within these levels, policymakers and researchers can gain insights into the challenges and opportunities associated with urbanization and plan for sustainable development.