Fire is a strong oxidation reaction that occurs during the combustion of a substance, and its energy is released in the form of light and heat, and a large amount of product is produced. Slow oxidation reactions, such as rust or digestion, are not in the definition above. The visible portion of the fire is called a flame and can have a different shape as the particles vibrate, and can appear in the form of a plasma (fourth state, like a gas) when the temperature is sufficiently high. The color and brightness of the flame will vary depending on the substance being burned and the purity. Fire must have combustibles, high enough heat or temperature, oxidants and chemicals to coexist in order to produce fire. Indispensable to the law, according to the law of conservation of mass, the fire will not make the atoms of the incineration disappear, but only through the chemical reaction The molecular form of the combustion. Fire is one of the important factors affecting the global ecosystem. The positive effects of fire can sustain various ecosystems and stimulate their growth. Humans use fire to cook, generate heat, generate signals, illuminate and propel. The negative effects of fire include water pollution, soil loss, air pollution and damage to life and property. One of the reasons for the greenhouse effect of rising global temperatures is the carbon dioxide produced by the burning of fossil fuels.