English: Tobacco is the common name of several plants in the Nicotiana genus and the Solanaceae (nightshade) family, and the general term for any product prepared from the cured leaves of the tobacco plant. More than 70 species of tobacco are known, but the chief commercial crop is N. tabacum. The more potent variant N. rustica is also used around the world.

Tobacco contains the stimulant alkaloid nicotine as well as harmala alkaloids.T Dried tobacco leaves are mainly used for smoking in cigarettes, cigars, pipes, shishas as well as e-cigarettes (both rechargeable and disposable), e-cigars, e-pipes and vaporizers. They can also be consumed as snuff, chewing tobacco, dipping tobacco and snus.

Tobacco use is a risk factor for many diseases; especially those affecting the heart, liver, and lungs, as well as many cancers. In 2008, the World Health Organization named tobacco use as the world's single greatest preventable cause of death.