Aside from lengthy definitions, different people and different angles will naturally have different understandings of smart cities. From the national level, smart cities pay more attention to the measurement, analysis and integration of key information needed for urban operation, and then make intelligent responses to various needs including people's livelihood, environmental protection, public security, urban services and industrial and commercial activities through big data analysis. It can be reflected not only in the convenience service of decentralization, but also in the maintenance of stability and security. By realizing the intelligent management and operation of the city, we can create a better life for people in the city and promote the harmonious and sustainable development of the city.