Hills are easier to climb than mountains. They are less steep and not as high. But, like a mountain, a hill will usually have an obvious summit, which is its highest point. According to the U.S. Geological Survey, there is no official difference between hills and mountains.
The contiguous United States are framed by three major bodies of water: the Atlantic Ocean on the east coast, the Pacific Ocean on the west and the Gulf of Mexico to the south. The Pacific also holds the Hawaiian Island chain. The Gulf stretches from Texas to Florida and also touches Alabama, Louisiana and Mississippi.
Energy security is the association between national security and the availability of natural resources for energy consumption. Access to (relatively) cheap energy has become essential to the functioning of modern economies.
