what are the requirements for a place to be called a city?

Question

we need the statistical records..

Answer 1

In the US, the answer varies from greatly state to state. See the Wikipedia article for "City" (http://en.wikipedia.org/wiki/City), particularly the section headed "the difference between towns and cities" and the the "United States" section within that section. Some states have a minimum required population for a city, while others don't.

Answer 2

it has to have a number of people and more than one light i mean traffic light