Tobacco is the agricultural product of the leaves of plants in the genus Nicotiana. All species of Nicotiana contain the addictive drug nicotine—a stimulant and sedative contained in all parts of the plants except the seeds—which occurs in varying amounts depending on the species and variety cultivated. See types of tobacco and curing of tobacco for more information.
The vast majority of commercially available tobacco is derived from the species Nicotiana tabacum, although it is also produced from Nicotiana alata, and to a lesser extent Nicotiana clevelandii, Nicotiana longiflora, and Nicotiana rustica, among others.
Once tobacco has been grown, harvested, cured, and processed, it is used to produce a number of different products. These are most often consumable; however, tobacco and the nicotine derived from it are also used to create pesticides.
Tobacco products can generally be divided into two types: smoked tobacco (see tobacco smoking ) and smokeless tobacco.
An expert in tobacco and tobacco products — especially pipes, pipe tobacco, and cigars—including their procurement and sale, is called a tobacconist.
The health effects of tobacco consumption are discussed in health effects of tobacco.
Chewing is one of the oldest methods of consuming tobacco leaves. Native Americans in both North and South America chewed the fresh leaves of the tobacco plant, frequently mixed with lime. Modern chewing tobacco (colloquially known as chew or chaw, especially in the American South and Midwest) is produced from cured and often fermented tobacco, usually dampened and mixed with some type of sweetener. (Often molasses.) Twist tobacco may be an exception in this case, as many brands of twist are not sweetened.