A smokeless cigarette [notes is an electronic device that replicates tobacco smoking cigarettes. It includes an atomizer, a source of power such as a battery, and a container such as a cartridge or tank. Instead of cigarette smoke, the user inhales vapor, so using an e-cigarette is called "vaping". The atomizer is a heating element that atomizes a liquid solution called e-liquid.  E-cigarettes are activated by taking a puff or pressing a button. Some look like conventional cigarettes. A lot of variations are multiple-use.
E-cigarettes develop an aerosol, frequently called vapor, made from particle matter. The vapor normally consists of propylene glycol, glycerin, nicotine, tastes, and traces of toxicants, carcinogens,  heavy metals, and metal nanoparticles. Its specific structure differs, and depends upon numerous aspects consisting of user habits.
The health results of electronic cigarettes are unknown,  but they are likely less harmful than smoking tobacco. E-cigarette vapor contains fewer toxic chemicals, in lower concentrations, than cigarette smoke. It does contain harmful chemicals, including harmful chemicals not discovered in tobacco smoke.
Nicotine is poisonous and extremely addicting. Youths are especially prone to this, and a lot of (90%) cigarette smokers begin before the age of 18. Among novice users of people who try nicotine become addicted.  People who vape are most likely to begin smoking cigarettes. For cigarette smokers, the finest recommendations is to stop, preferably using cigarette smoking cessation therapy such as NRT. However, for those smokers who are not able or reluctant to give up utilizing traditional NRT, vaping has a role in tobacco harm reduction.
An electronic cigarette consists of an atomizer, a source of power such as a battery, and a container for the e-liquid such as a cartridge or tank.
First-generation e-cigarettes tend to appear like standard cigarettes, though there is some variation in size, therefore are called "cigalikes". Second-generation devices are larger overall and look less like traditional cigarettes. Third-generation gadgets consist of mechanical mods and variable voltage gadgets.  The fourth-generation consists of Sub ohm tanks (meaning that they have electrical resistance of less than 1 Ohm) and temperature control devices. The voltage for first-generation e-cigarettes has to do with and second-generation e-cigarettes can be changed from 3 V to 6 V, while more current devices can go up to 8 V. There are also pod mod devices that use protonated nicotine, instead of free-base nicotine discovered in earlier generations, offering higher nicotine yields through the production of aerosolized protonated nicotine.
E-liquid is the mixture used in vapor items such as e-cigarettes. It generally includes propylene glycol, glycerin, nicotine, flavorings, additives, and contaminants. E-liquid formulations differ extensively. A common e-liquid makes up propylene glycol and glycerin (95%), and flavorings, nicotine, and other additives (5%). Some e-liquids do not have propylene glycol,  nicotine, or flavors.The flavorings might be natural, synthetic, or organic.Over 80 chemicals such as formaldehyde and metallic nanoparticles have been discovered in the e-liquid. There are lots of e-liquid producers, and more than 15,000 flavors. 
In the US, under Fda (FDA) guidelines, e-liquids should abide by producing standards.Industry standards are published by the American E-liquid Production Standards Association (AEMSA). EU requirements are in the EU Tobacco Products Regulation.
Numerous users begin with a disposable e-cigarette resembling a tobacco cigarette.   They frequently progress to later-generation devices and may adjust their devices to provide more vapor.Experienced users often prefer rechargeable e-cigarettes.  Women choose non reusable e-cigarettes, and young adults pay more attention to modifiability. Modifiability increases the chance of beginning vaping among youths.
The majority of vapers utilize a refillable tank system, allowing them to mix their own liquid offering control over flavor and strength.Experienced vapers rank customizability as the most important website factor to consider in selecting a device. Users ranked nicotine strength as a crucial element for selecting among numerous e-cigarettes, though such preference could differ by cigarette smoking status, e-cigarette use history, and gender.Non-smokers and unskilled e-cigarettes users tended to prefer no nicotine or low nicotine e-cigarettes while smokers and knowledgeable e-cigarettes users preferred medium and high nicotine e-cigarettes.