| Terms | Definition | Researcher | Examples |
| Sustainable City | It stimulates social equity, economic productivity, and environmental quality to meets the needs of the present without compromising the ability of future generations to meet their own needs. | Riviere et al.,2013 [43] Liu et al., 2016 [44] | 1) Malmö, Sweden |
| Eco-city | A city where human beings can exist in harmony with nature therefore greatly reducing ecological footprint. A city that creates economic opportunities for their citizens in an inclusive, sustainable, and resource-efficient way, while also protecting and nurturing the local ecology and global public goods, such as the environment, for future generations. | Suzuki et al. 2010 [45] World Bank, 2015 [46] | 1) Sino-Singapore Tianjin Eco-city, China 2) City of Copenhagen, Denmark 3) Stockholm, Sweden 4) Yokohama, Japan |
| Smart city | The safe, secure, environmental and efficient urban center of the future with advanced information and communication technologies (ICT) to stimulate sustainable development in the economic growth and a high quality of life | UNESCAP, 2012 [47] Sarker, 2017 [48] | 1) Barcelona, Spain 2) Luxembourg |
| Carbon neutral city | Similar to “LCC” except defined more strictly as a city which has zero carbon emissions. | Adelaide City Council, 2015 [49] | 1) Melbourne, Australia |
| Zero carbon city | More specifically to a city which produces no GHG and is run exclusively on energy from renewable sources | Urban World, 2009 [50] Hannallah & Faragallah, 2009 [50] | 1) Masdar City, United Arab Emirates 2) Dongtan, China |