Marijuana is a flowering plant of cannabis family. The number of species in this genus is controversial. Three may be recognized: alfalfa, Indian marijuana and Rudd marijuana. Yun can be included in alfalfa. Or consider all three species as subspecies of a single species (C. sativa). The genus is indigenous to Central Asia and the Indian subcontinent.

Marijuana has long been used in hemp fiber, sesame oil, medicine and leisure medicine. Industrial cannabis products are made from cannabis plants, which are selected to produce a large number of fibers. In order to meet the requirements of the United Nations Convention on narcotic drugs, some strains of cannabis have been developed to produce the lowest level of THC, the main psychoactive ingredient. Many plants have been selectively bred to produce the largest tetrahydrocannabinol (cannabinoid), which is obtained by solidifying flowers. Various compounds were extracted from plants, including hemp oil and hemp oil.

Globally, 60400 kg of cannabis were legally produced in 2013. In 2014, there were an estimated 182.5 million cannabis users (3.8 per cent of the population aged 15-64). There was no significant change in this percentage between 1998 and 2014.