According to Wikipedia, an electronic cigarette or "e-cigarette" is an alternative to smoked tobacco products, such as cigarettes, cigars, or pipes. It is a battery-powered device that provides inhaled doses of nicotine by delivering a vaporized propylene glycol/nicotine solution. In addition to nicotine delivery, this vapor also provides a flavor and physical sensation similar to that of inhaled tobacco smoke, while no tobacco, smoke, or combustion is actually involved in its operation.