"Tetrahydrocannabinol (THC) is one of the phytocannabinoids found in the trichomes on cannabis flowers. THC causes psychoactive effects by mimicking the endocannabinoid anandamide, which is produced naturally within the body. The THC molecule is derived from terpenes, which can be very aromatic and even provide medical benefits.
THC was first described and published in 1964 in the Journal of the American Chemical Society. The main chemical structure of THC is (Δ9-tetrahydrocannabinol). THC remains on the list of Schedule-1 drugs in the United States, meaning the US government believes that neither THC nor cannabis can provide medical benefits. Researchers from Israel, Spain, and other countries with sensible cannabis policies suggest that THC may have many medical benefits:
More research is required to improve our understanding of how exactly THC works, although it does have an equal affinity for both CB1 and CB2 receptors of the endocannabinoid system. THC is currently the most common cannabinoid available on dispensary shelves."