An explosive is a substance or mixture that undergoes a rapid, highly exothermic decomposition, resulting in the sudden generation of a large volume of hot gas and often light. Chemically, this rapid reaction is driven by the formation of stable gaseous products, leading to an extremely high pressure wave. The energy released must be significantly greater than the chemical potential energy stored within the initial reactants. The speed and intensity of the decomposition, which determine the material's explosive classification, are governed by the chemical structure, energy density, and the reaction kinetics, necessitating conditions that promote a supersonic speed of decomposition front.