In the United States, the government legally defines a city, and a town is simply a community with no official legal government standing. Each country legally defines these terms differently, however.
Voters have to create and approve a city. State and county laws govern what a city can and can’t do. Towns, villages, communities or any other collection of people that are unincorporated have no legal standing by themselves. This means that county governments have to provide services to these groups instead, usually on an unofficial basis. There are exceptions since some states actually define what a town means legally and give this legal standing some powers.
Outside of legal terms, the term city is often just used to describe an area that is densely populated enough to be considered urban by its home country. Each country has a different idea of what makes an area urban. For example, in Sweden the minimum population for describing an area as urban is 200 inhabitants. As a result, 83 percent of the Swedish population is urban. In Japan, it takes 30,000 citizens before a population is considered urban near a city, and so only 78 percent of its population counts. Some cities actually use the name “town” even though they are still a city.