Smart cities aim to achieve high levels of liveability and sustainability for urban inhabitants. Many global cities and metropolises have already benefited from new infrastructure and technologies associated with intelligent and smart planning. Creating smart cities is a good response as they incorporate well-advised approaches towards the environment. 'Smart cities' can help in saving the planet. It is impossible to debate smart cities and consciousness without requiring people's engagement. Technology leaders such as IBM, Cisco, Siemens and others are planning for smart cities that inspire a breakthrough. Global cities and world cities are undergoing continuous evolution. Global Smart City Industry is the name of a report that analyses the worldwide markets for smart cities. Having the issue of a lack of a clear definition for smart cities, the International Telecommunication Union (ITU), a specialized agency of the United Nations (UN), analysed 116 definitions for smart cities in a comprehensive report.