You are required to build and maintain a city. You must feed, house,
provide jobs and goods for your residents. You can build a sustainable
economy with the help of renewable energy and recycling, or you can go for
broke and build rockets to escape from a pollution ridden and resource
starved planet, it's up to you. Due to the finite resources available in
any one place, this is not a game that you can leave for long periods of
time.