E-cigarettes are a type of atomizer powered by a lithium polymer battery, which heats the electronic liquid in the atomized oil tank (also known as e-liquid, e-juice, E-liquid or E-juice; e-liquid contains 1, 2-propanediol, vegetable glycerin, food flavor or nicotine, and nicotine can be added without adding). Electronic cigarettes do not need to be burned, they only produce "steam" and there is no tar or carbon monoxide.