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'''Coal''' is a combustible material which was formed by decomposing plant and animal material placed under intense pressure.

'''Coal''' is a combustible material which was formed by decomposing plant and animal material placed under intense pressure.

The [[Coal mining|mining]] of coal as a [[fuel]] was essential for the [[Industrial Revolution]], as coal was used to power [[factory|factories]] and [[railway]]s, first through the generation of steam, and later when coal became one of several methods of generating [[electricity]].

[[Coal mining]] is the extraction of coal for use as a [[fuel]]. It became important after 1800 as coal fueled railroads of the [[Industrial Revolution]], and (where cheap water power was not available), the factories. Coal is now the chief method of generating [[electricity]], along with burning natural gas, using water power in dams, and using nuclear energy.

Laboratory experiments show that coal can be formed in a matter of months, and with temperatures in the range of 100 to 150 degrees Celsius (210-300 degrees Fahrenheit) for brown coal and 400 degrees Celsius (750 degrees Fahrenheit) for black coal.<ref>Quoted by Walker, 2001</ref>

Laboratory experiments show that coal can be formed in a matter of months, and with temperatures in the range of 100 to 150 degrees Celsius (210-300 degrees Fahrenheit) for brown coal and 400 degrees Celsius (750 degrees Fahrenheit) for black coal.<ref>Quoted by Walker, 2001</ref>