The primary reason as to why you feel ‘high’ after smoking marijuana is because of the presence of a substance called THC, which stands for tetrahydrocannabinol. THC is a compound which naturally occurs in marijuana plants and carries psychoactive properties. When you smoke weed, the THC present in it combines with your body’s endocannabinoid system and interacts with your cannabinoid receptors. Once this happens, neurotransmitters are released into your brain which is what alters the sense of reality and makes you feel the ‘high’ that you are getting out of smoking weed.