Cannabis plants produce over 180 known cannabinoids, with cannabidiol (CBD) being one of those. THC (primary psychoactive component in cannabis) is also a cannabinoid. Other documented, but less researched cannabinoids include: cannabigerol (CBG), cannabinol (CBN), cannabichromene (CBC) and many others.
All mammals have an endocannabinoid system (ECS) that is activated by substances in our bodies called endocannabinoids. Phytocannabinoids are substances like CBD that are produced by plants and function at the same receptors in the ECS. At this time there are two well-known receptors, CB1 and CB2. CB1 receptors are found in high numbers in our brain and central nervous system. CB2 receptors are found in high density in our immune systems. Other locations of CB1 and CB2 receptors include skin, liver, bone, and the gastrointestinal tract. The majority of CBD's mechanism of action is still being studied.