A smart city' is an urban area that uses digital technology to collect data and to operate/provide services. Data can be collected from citizens, devices, buildings, or cameras. Applications include traffic and transportation systems, power plants, utilities, urban forestry, water supply networks, waste disposal, criminal investigations, information systems, schools, libraries, hospitals, and other community services. The foundation of a smart city is built on the integration of people, technology, and processes, which connect and interact across sectors such as healthcare, transportation, education, and infrastructure, etc. Smart cities are characterized by the ways in which their local governments monitor, analyze, plan, and govern the city. In a smart city, the sharing of data extends to businesses, citizens and other third parties who can derive benefit from using that data. The three largest sources of spending associated with smart cities as of 2022 were visual surveillance, public transit, and outdoor lighting.