An electronic cigarette or e-cigarette is a handheld electronic device that vaporizes a flavored liquid. The user inhales the vapor. Using e-cigarettes is often called vaping. The fluid in the e-cigarette, called e-liquid, is usually made of nicotine, propylene glycol, glycerine, and flavorings. The health risks of e-cigarettes are uncertain. While they are likely safer than tobacco cigarettes, the long-term health effects are not known.