Cannabis, also known as marijuana or weed among other names, is a psychoactive drug from the cannabis plant. Native to Central or South Asia, the cannabis plant has been used as a drug for both recreational and entheogenic purposes and in various traditional medicines for centuries. Tetrahydrocannabinol (THC) is the main psychoactive component of cannabis, which is one of the 483 known compounds in the plant, including at least 65 other cannabinoids, such as cannabidiol (CBD). Cannabis can be used by smoking, vaporizing, within food, or as an extract.

Cannabis has various mental and physical effects, which include euphoria, altered states of mind and sense of time, relaxation, pain relief, and an increase in appetite. Onset of effects is felt within minutes when smoked, but may take up to 90 minutes when eaten (as orally consumed drugs must be metabolized). The effects last for two to six hours, depending on the amount used.