Marijuana (grass, pot, weed) is the common name for a crude drug made from the Cannabis plant. The main mind-altering (psychoactive) ingredient in marijuana is THC (delta-9-tetrahydrocannabinol), but more than 400 other chemicals also are in the plant. A marijuana “joint” (cigarette) is made from the dried particles of the plant.
The amount of THC in the marijuana determines how strong its effects will be. The...