Regulation of electronic cigarettes varies across countries and states, ranging from no regulation to banning them entirely. As of 2015, around two thirds of major nations have regulated e-cigarettes in some way. A 2023 report by the World Health Organization (WHO) found that 34 countries had banned the sale of e-cigarettes.

An electronic cigarette (e-cigarette) or vape is a device that simulates tobacco smoking. It consists of an atomizer, a power source such as a battery, and a container such as a cartridge or tank. Instead of smoke, the user inhales vapor. As such, using an e-cigarette is often called "vaping". The atomizer is a heating element that vaporizes a liquid solution called e-liquid, which quickly cools into an aerosol of tiny droplets, vapor and air. The vapor mainly comprises propylene glycol and/or glycerin, usually with nicotine and flavoring. Its exact composition varies, and depends on several things including user behavior.