Cannabis (/ˈkænəbɪs/) is a genus of flowering plant that includes three species (and seven taxa) or subspecies,sativa, indica, and ruderalis. The plant is indigenous to central Asia and the Indian subcontinent.

Cannabis has long been used for hemp fibre, for hemp oils, for medicinal purposes, and as a recreational drug. Industrial hemp products are made from cannabis plants selected to produce an abundance of fiber. To satisfy the UN Narcotics Convention, some cannabis strains have been bred to produce minimal levels of tetrahydrocannabinol(THC), the principal psychoactive constituent. Many plants have been selectively bred to produce a maximum of THC (cannabinoids), which is obtained by curing the flowers. Various compounds, including hashish and hash oil, are extracted from the plant. Globally, in 2013, 60,400 kilograms of cannabis were produced legally. In 2013 between 128 and 232 million people are thought to have used cannabis as a recreational drug (2.7% to 4.9% of the global population between the ages of 15 and 65).



Modern history
In the mid 19th century, medical interest in the use of cannabis began to grow in the West. In the 19th century cannabis was one of the secret ingredients in several so calledpatent medicines. There were at least 2000 cannabis medicines prior to 1937, produced by over 280 manufacturers.