feu

Feu, commonly translated as fire, is the rapid oxidation of a material accompanied by the release of heat, light, and reaction products. For a fire to start and continue, three elements must be present: heat, fuel, and an oxidizer. Together they form the fire triangle, a useful model for understanding ignition and extinguishing.

The visible part of a fire is the flame, a region of hot gases where combustion occurs. Flame color and temperature depend on the chemical species involved and the oxygen supply. Fire can be natural, such as wildfires fueled by vegetation, or human-caused, such as cooking, heating, or industrial processes.

Combustion can be complete or incomplete. Complete combustion with plenty of oxygen yields primarily carbon dioxide and water; incomplete combustion releases carbon monoxide, soot, and other pollutants, and produces more visible smoke and heat.

Safety and control are central to the study of feu. Fires pose risks of burns, smoke inhalation, and structural damage. Prevention includes proper handling of fuels, electrical safety, and smoke detectors. Extinguishing a fire typically involves removing heat, starving the fuel, or cutting off the oxidizer; agents include water, foams, dry chemical powders, and carbon dioxide, chosen to suit the fuel type.

Historically, mastery of fire has shaped technology, industry, and culture, from cooking and heating to metalworking and power generation. Fire remains a core concept in physics and chemistry, as well as a major public safety concern and environmental factor in many regions.