The medieval city of Sienna with its town square and magnificent town hall. A modern suburb can be seen in the background.
A city is a place where many people live together.
A city has many buildings and streets. It has houses or apartments for many people to live, shops where they may buy things, places for people to work and a governmentorganisation to run the city, and to keep law and order in the city. People live in cities because it is easy for them to find and do the things they want there. A city usually has a "city centre" where government and business take place, and places called suburbs where people live around the outside of the centre.
There is no rule that is used all over the world to decide why some places are called "city" and other places are called "town".
Some things that make a city are:
A long history. Although many cities today have only been around for tens or hundreds of years, there are a few which have been so for thousands of years. For example, Athens, Greece was founded in 1000 BC and Rome, Italy has existed since 700 BC.