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what is smoking?

no smoking signsmoking is one of the most common forms of recreational drug use. it is a habit which consists of breathing in a smoke from a burned substance. this substance contains the active alkaloid nicotine which is absorbed into the bloodstream. it may cause various diseases and dysfunctions. tobacco smoking is the most popular form of smoking. it is practiced by over one billion people globally, of whom the majority are in the developing world. 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 substances is very limited as they are usually not commercially available.

 

history of smoking

the practice of 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 various religious purposes. after the european exploration and conquest of the americas, the practice of smoking tobacco quickly spread to the rest of the world.

 

smoking and health problems

smoking has negative health effects, because smoke inhalation inherently poses challenges to various physiologic processes such as respiration. diseases related to tobacco smoking have been shown to kill approximately half of long term smokers when compared to average mortality rates faced by non-smokers. a 2007 report states that, each year, about 4.9 million people worldwide die as a result of smoking. it is among the leading causes of many diseases such as lung cancer, heart attacks, erectile dysfunction, and birth defects. the health hazards of smoking have caused many countries to institute high taxes on tobacco products, run ads to discourage use, limit ads that promote use, and provide help with quitting for those who do smoke