Smoking is a practice in which a substance, most commonly tobacco, is burned and the smoke tasted or inhaled. This is primarily practiced as a route of administration for recreational drug use, as combustion releases the active substances in drugs such as nicotine and makes them available for absorption through the lungs. The most common method of smoking today is through cigarettes, primarily industrially manufactured but also hand-rolled from loose tobacco and rolling paper. Other smoking tools include pipes, cigars and hookahs.
Smoking is one of the most common forms of recreational drug use. Tobacco smoking is today by far the most popular form of smoking and is practiced by over one billion people in the majority of all human societies.
Smoking is injurious to health. Smoking harms nearly every organ of the body. Cigarette smoking causes lung cancer. It is also responsible for many other cancers and health problems. These include lung disease, heart and blood vessel disease, stroke and cataracts. Women who smoke have a greater chance of certain pregnancy problems or having a baby die from sudden infant death syndrome (SIDS). Smoke is also bad for other people - they breathe in secondhand smoke and can get many of the same problems as smokers do- Passive smoking.
Quitting smoking can reduce risk of these problems.