For all your vaping needs

In general terms, an electronic cigarette (e-cigarette or ecig) uses an atomizer (coil) to vaporize a liquid mixture into a smoke-like vapor that is inhaled into the lungs.  This delivers the nicotine into the lungs in the same way that cigarette smoke does, only without the over 4000 chemical compounds that are found in traditional "analog" cigarettes.

A re-chargeable lithium-ion battery supplies power to the atomizer.  While activated, current flows through the element of the atomizer which produces enough heat to vaporize the liquid.  Because of the work done by the atomizer, they do require replacement.