If you live in one place and work some distance away, such that you have to take a train or a bus, then you will be called a commuter. You are really a commuter if you have to do this to get to school, but it is mostly meant for those millions of people who have to make a daily journey from home in the country or suburbs into the centre of a city or some other place like an industrial estate.
Commuting is expensive. It can also be a nightmare because most people commute at the same time, resulting in crowded buses and trains and a constant demand for more and more trains and buses.