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According to the article by Moreno, a city is defined as something beyond a simple geographical territory with territorial limits, but rather the city encompasses a series of elements that significantly affect the achievement of sustainable development objectives if they are managed. The statistical meaning of what establishes the city isn't a simple assignment. This entangles the estimation of its population. The City Proper is regularly the littlest unit of investigation and alludes to the zone kept as far as possible. It is the single political locale which is a piece of the authentic city community. With barely any special cases, the 'City Proper" is an exceptionally thin regulatory boundary of the city and doesn't consider nearby regions of the city and rustic regions that are remembered for the urban degree of the city (Moreno, 3). As much as 38% of countries utilize another idea that is the 'city proper'. It is evaluated that one-fifth of countries consolidate different definitions to appraise city and population information in their urban zones. Almost 5% of extra countries utilize an alternate rule to characterize their urban populations, which is the "metropolitan region".