Cannabis, also known as marijuana (from the Mexican Spanish marihuana), and by numerous other names, is a preparation of the Cannabis plant intended for use as a psychoactive drug and as medicine. Pharmacologically, the principal psychoactive constituent of cannabis is tetrahydrocannabinol (THC); it is one of 483 known compounds in the plant, including at least 84 other cannabinoids, such as cannabidiol (CBD), cannabinol (CBN), tetrahydrocannabivarin (THCV), and cannabigerol (CBG).
Cannabis is often consumed for its psychoactive and physiological effects, which can include heightened mood or euphoria, relaxation, and increase in appetite. Unwanted side-effects can sometimes include a decrease in short-term memory, dry mouth, impaired motor skills, reddening of the eyes, and feelings of paranoia or anxiety.
Contemporary uses of cannabis are as a recreational or medicinal drug, and as part of religious or spiritual rites; the earliest recorded uses date from the 3rd millennium BC. Since the early 20th century cannabis has been subject to legal restrictions with the possession, use, and sale of cannabis preparations containing psychoactive cannabinoids currently illegal in most countries of the world; the United Nations has said that cannabis is the most-used illicit drug in the world. In 2004, the United Nations estimated that global consumption of cannabis indicated that approximately 4% of the adult world population (162 million people) used cannabis annually, and that approximately 0.6% (22.5 million) of people used cannabis daily.
Cannabis (//) is a genus of flowering plants that includes three putative varieties, Cannabis sativa, Cannabis indica, and Cannabis ruderalis. These three taxa are indigenous to Central Asia, and South Asia. Cannabis has long been used for fibre (hemp), for seed and seed 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 THC, the principal psychoactive constituent responsible for the "high" associated with marijuana. Marijuana consists of the dried flowers of Cannabis plants selectively bred to produce high levels of THC and other psychoactive cannabinoids. Various extracts including hashish and hash oil are also produced from the plant.
Cannabis sativa is an annual herbaceous plant in the Cannabis genus, a species of the Cannabaceae family. People have cultivated cannabis sativa throughout recorded history as a source of industrial fibre, seed oil, food, recreation, religious and spiritual enlightenment, and medicine. Each part of the plant is harvested differently, depending on the purpose of its use.