C. sativa L. subsp. sativa C. sativa L. subsp. indica

Cannabis, also known as marijuana, marihuana, and ganja (from Sanskrit: गांजा gañjā, hemp)a[›], refers to any number of preparations of psychoactive drug from the Cannabis plant. The most common form is the natural herbal form.

The herbal form of the drug consists of mature female flowers and sub-tending leaves of pistillate (female) plants. The resinous form, known as hashish, consists primarily of glandular trichomes collected from the same plant material. The major psychoactive chemical compound in Cannabis is Δ9-tetrahydrocannabinol (delta-9-tetrahydrocannabinol), commonly referred to as THC. At least 66 other cannabinoids are present in Cannabis, such as cannabidiol (CBD) and cannabinol (CBN). Many of these cause some psychoactive interactions.

Marijuana is seen in strains of either pure breeds or intra-specific hybrids of Cannabis, typically of the subspecies indica or sativa. Strains are developed to highlight a specific combination of properties of the plant or to establish marketing differentiation.

The human consumption of Cannabis smoke is found as long ago as the 3rd millennium BC. In modern times, the drug has been used for recreational, religious or spiritual, and medicinal purposes. The United Nations estimates that about four percent of the world's adult population (162 million) use cannabis annually and about 0.6 percent (22.5 million) daily. The possession, use, or sale of psychoactive Cannabis products became illegal in most parts of the world in the early 20th century. Since then, some countries have intensified the enforcement of cannabis prohibition while others have reduced the priority of enforcement.

For more information about Cannabis (drug), read the full article at Wikipedia.
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