The illustration below is a great infographic. The History of Energy shows how essential energy and fuel have been to human survival and existence. As far back as 770,000 B.C., humans discovered fire, perhaps worshiped it as a god. And I have to say, not much has changed. Only these days, it's not fire so much as it is energy in the form of oil — despite the fact that windmills were invented in 1000 A.D.
Photo: Roz Woodward/Getty Images