An e-cigarette comprises battery, atomizer, heating coil and a reservoir for the liquids used for producing vapour.
The mechanism is activated either by pressing a button or by suction. Liquids come with or without nicotine, and also contain aromas and flavours like amaretto, almond, vanilla or apple.
These liquids are heated up in the atomizer and vaporized at between 65 and 120 degrees Celsius. Propylene glycol is the most usual solvent; it produces the atomized mist that resembles smoke, according to a Fraunhofer statement.
An estimated two million people in Germany have already turned to the vapour cigarette.