Smoking is a practice in which a substance, most commonly tobacco or cannabis, is burned and the smoke tasted or inhaled. This is primarily practised 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.It has been suggested that smoking related disease kills one half of all long term smokers but these diseases may also be contracted by non-smokers. A 2007 report states that about 4.9 million people worldwide each year die as a result of smoking.
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. Less common drugs for smoking include cannabis and opium. Some of the substances are classified as hard narcotics, like heroin, but the use of these is very limited as they are often not commercially available.
Smoking can be dated to as early as 5000 BC, and has been recorded in many different cultures across the world. Early smoking evolved in association with religious ceremonies; as offerings to deities, in cleansing rituals or to allow shamans and priests to alter their minds for purposes of divination or spiritual enlightenment.
The practice of smoking tobacco quickly spread to the rest of the world. In regions like India and Subsaharan Africa, it merged with existing practices of smoking (mostly of cannabis). In Europe, it introduced a new type of social activity and a form of drug intake which previously had been unknown.
Perception surrounding smoking has varied over time and from one place to another; holy and sinful, sophisticated and vulgar. Today medical studies have proven that smoking tobacco is among the leading causes of many diseases such as lung cancer, heart attacks, erectile dysfunction and can also lead to birth defects. The inherent health hazards of smoking have caused many countries to institute high taxes on tobacco products and anti-smoking campaigns are launched every year in an attempt to curb tobacco smoking.