combustion

Combustion is the chemical term for a process known more commonly as burning. It is one of the earliest chemical changes noted by humans, due at least in part to the dramatic effects it has on materials. Early humans were probably amazed and frightened by the devastation resulting from huge forest fires or by the horror of seeing their homes catch fire and burn.
 But fire (combustion)—when controlled and used correctly—was equally important to their survival, providing a way to keep warm and to cook their meals.