Fire is the rapid oxidation of a material (the fuel) in the exothermic chemical process of combustion.
Fire in its most common form can result in conflagration, which has the potential to cause physical damage
Once ignited, a chain reaction must take place whereby fires can sustain their own heat by the further
release of heat energy in
the process of combustion and may propagate, provided there is a continuous supply of an oxidizer and fuel.
A flame is a mixture of reacting gases and solids emitting visible, infrared, and sometimes ultraviolet
light, the frequency
spectrum of which depends on the chemical composition of the burning material and intermediate reaction