The theory of Continental Drift suggest that hundreds of years ago all the continents were one big continent called Pangea. Soon these contintents split up created the places that we live today. This theory was introduced by Alfred Wegener. His colleges thought he was crazy, but later studies proved his impossible theory to be true. By the process of "sea floor spreading" the continents were then ripped apart and drifted to where they are today.
they are abundant and accessible, they provide a large amount of concentrated energy. They are also relatively low cost and they can be transported relatively easily.
