An explosive is a chemical compound or mixture that undergoes rapid combustion and produces heat, gas, and pressure effects. The earliest explosive compound known was gunpowder, which was first used in the 13th century, and was the only explosive known for hundred of years. The first modern explosive, a compound known as nitroglycerin, was discovered in 1846. Compounds similar to nitroglycerin are the most commonly used explosives today. Explosives vary in brisance, or shattering effect, and in their stability under various enviornmental conditions. Aside from their obvious use in weaponry, explosives are also used in such peaceful applications as rocket propellants and for mining and demolition work.