**4. The transportation sector**

The present prosperity of the world is much dependent on the rapid transportation of people across large distances. The transportation sector involves the automobile, trucking, locomotive (train), shipping and aviation industries. The vast majority of this transportation industry runs on oil. The exceptions are mass transit, such as city trains running on electricity, and large defense ships running on nuclear power. There is an ongoing transition from oil to natural gas power and electric power for automobiles.
