An E-Cigarette is a cigarette-sized tube with a colored LED light on the end, containing a battery and an atomizer cartridge that holds liquid. The solutions are often referred to as e-liquid or e-juice. Typically, they contain hundreds of flavors. For those desiring nicotine without smoke, the solution contains nicotine dissolved in propylene glycol and/or vegetable glycerin - both common food additives. Nicotine doses in the cartridges are rated in low, medium, high, and zero nicotine. The high strength cartridge has the nicotine equivalent of a regular cigarette, though some have been known to exceed that. More at http://krazyvapors.com/vaping/vaping-v-smoking-show-pros-cons-new-infographic/