Coal mining has a history spanning thousands of years. It became particularly important during the Industrial Revolution of the nineteenth and twentieth centuries when it was extensively used to power steam engines, provide heating, and generate electricity. Even today, coal mining remains a key economic activity. Coal produces more energy per mass than wood fuels and is frequently available in places where wood is difficult to come by. Although historically used as a residential fuel, coal is currently mostly employed in industry, particularly in the manufacturing of alloys and smelting, as well as in the creation of electricity. This chapter gives a thorough introduction to coal and its background, history, and chemistry. Hydrogen, oxygen, nitrogen, ash, and sulfur are all present in coal. In terms of coal burning, it produces more ash and sulfur, which are problematic for both the environment and human health.