Herbert A. Gilbert came up with the concept of

Popularly known as a smokeless non-tobacco cigarette, this type of cigarette offers a method of smoking that is not only safe but harmless as well. This cigarette uses heated, moist, flavored air instead of burning tobacco and paper which makes it harmless. This device took lot of time in reaching manufacturing stage because of the limitations of available technology available. Chinese pharmacist Hon Lik invented the modern electronic cigarette in 2003 and the following year it was introduced to the market. Electronic cigarette is an electrical device which is used for the simulation of tobacco smoking and people can use it and enjoy smoking through this act of simulation. When used this electronic cigarette produces an inhaled mist thereby offering a physical sensation and appearance of regular cigarette. Heat or ultrasonic is used by this device to vaporize a propylene glycol- or glycerin-based liquid solution into an aerosol mist. It is very much similar to the function of a vaporizer or nebulizer that vaporizes solutions for inhalation. The most important advantage of such cigarettes is that it avoids harmful impacts of regular cigarettes. These electronic cigarettes can be carried anywhere and their shape is self-contained cylindrical device matching a ballpoint pen or magic marker size. Due to different capacities of battery, the sizes of these electronic cigarettes may vary. To resemble actual cigarettes or cigars, or even pipes, many electronic cigarettes are designed. Some of these electronic cigarettes can be reused and some of its parts can be replaced and refilled but conversely some models are disposable variety. It is basically a harmless alternative to tobacco smoking. It can also be used as smoking cessation device. This device helps in avoiding the adverse health effects that are associated with tobacco smoke. Although some of these devices still carry health risks and could also appeal to non-smokers, like children. People may get attracted towards its novelty, safety and flavorings. Various health related organizations and researchers disagree on the advantages and disadvantages of electronic cigarettes and their use. Because of its relatively recent invention followed by rapid growth in popularity, there is scarcity of controlled studies in the field of electronic cigarettes. There are three major components in electronic cigarettes. These components are cartridge, atomizer and power supply. The function of cartridge is that it acts like a mouthpiece and also functions as a small reservoir that holds the liquid that is to be vaporized. On the other hand, atomizer serves as the device responsible for vaporizing the liquid acts as a heating element. Battery acts as a power supply, which is used in several portable models. Within the power unit, other electronic components necessary for operation are housed.