Combustion is a rapid chemical process that involves the reaction of a substance (the fuel) with an oxidizing agent, typically oxygen, in the presence of sufficient heat to initiate the reaction. This reaction is highly exothermic, meaning it releases significant amounts of energy in the form of heat and light, along with various gaseous products. The fundamental requirements for combustion—the fuel, the oxidizer, and the minimum required temperature—are often described by the fire triangle. Depending on the reactants, the byproducts can include carbon dioxide, water vapor, and nitrogen oxides. Beyond simple burning, the principles of controlled combustion are vital in various technological and biological systems, providing usable energy for everything from power generation to the metabolic processes that sustain life.