Fire is an irreversibly destructive process of combustion, manifested in heat and light, in which a highly organised structure of organic substances is reduced to smoke and ashes. In industrial situations fires are controlled spatially in the firebox (see also grates, Dutch Oven, dog house etc.) and in their heat release characteristics. In uncontrolled situations: e.g house fire, forest fire etc., the effect is very evidently destructive to life and property.