Combustion Theory explains the chemical process of burning, where a fuel reacts with an oxidant, typically oxygen, to produce heat and light. This reaction results in the formation of products like carbon dioxide and water vapor. The process can be classified into complete combustion, where fuel burns efficiently, and incomplete combustion, which occurs when there is insufficient oxygen. The theory also involves understanding the conditions necessary for combustion, including the fuel, oxidizer, and an ignition source, often referred to as the fire triangle. Combustion is essential in various applications, from powering engines to heating homes.