An electronic cigarette, also known as an e-cigarette, personal vaporizer PV, is an electronic inhaler that vaporizes a liquid solution into an aerosol mist, simulating the act of tobacco smoking. Electronic cigarettes are no longer marketed as smoking cessation aids or tobacco replacement in most countries. There may be similarities between conventional and some electronic cigarettes in the physical design and the nicotine release, which may approximate the same amount of nicotine as a conventional cigarette. There are many electronic cigarettes that do not resemble conventional cigarettes at all.
The benefits and risks of electronic cigarette use are uncertain among health organizations and researchers. Limited controlled studies are available due to its recent invention. Laws vary widely concerning the use and sale of electronic cigarettes and accompanying liquid solutions, with pending legislation and ongoing debate.