Urbanization refers to the process by which towns and cities are formed and become larger as more people live and work in central areas. The document identifies several causes of urbanization, including industrialization which creates jobs, economic development, and social services available in cities. Positive effects include technological advancement and improved living standards, but urbanization can also lead to overpopulation, the spread of diseases, and the formation of slums due to lack of infrastructure. Without proper planning, urbanization results in negative consequences such as stress-related health issues, crime, unemployment, and terrorism. The document recommends building sustainable cities through population control, provision of essential services, and environmentally-friendly urban planning and development.