The most abundant type of coal in the United States is bituminous coal. Bituminous coal is a high-energy coal that is commonly used for generating electricity and industrial purposes. It is found in large reserves in the Appalachian Region, the Midwestern United States, and the Western United States. Bituminous coal is characterized by its dark brown or black color and high carbon content. It has a higher energy content compared to other types of coal, such as lignite and sub-bituminous coal, and is commonly used in power plants due to its high heat value and relatively low sulfur content compared to other coal types.