CBD stands for cannabidiol. It is the second most prevalent of the active ingredients of cannabis (marijuana). While CBD is an essential component of medical marijuana, it is derived directly from the hemp plant, which is a cousin of the marijuana plant. While CBD is a component of marijuana (one of hundreds), by itself it does not cause a “high.” According to a report from the World Health Organization, “In humans, CBD exhibits no effects indicative of any abuse or dependence potential…. To date, there is no evidence of public health related problems associated with the use of pure CBD.”
Cannabinoids are naturally occurring compounds that interact with receptors found throughout the body to achieve certain physiological effects. Scientists have identified over 100 different cannabinoids in the cannabis plant, but the ones you'll most commonly hear about are delta-9-tetrahydrocannabinol (THC) and cannabidiol (CBD). Humans, along with all vertebrates like dogs, cats, fish, and birds, produce endocannabinoids — neurotransmitters that bind to receptors and impact pain, mood, appetite, sleep, and a variety of other functions. Exogenous cannabinoids, meanwhile, aren't produced by the body but can be found in marijuana as THC, CBD, and a variety of other compounds.
THC has an affinity to bind to CB1 receptors: It won't shut off your breathing or heart like opioids do because it doesn't affect the brain stem, but it does trigger that euphoric "high" feeling.
CBD, on the other hand, has a stronger affinity to CB2 receptors, which is why it can reduce inflammation without being psychoactive. Most CBD products, whether a tincture to help you sleep at night or a shot of oil in your smoothie, won't get you high if it's hemp-derived because hemp products cannot legally be sold if they contain a THC content higher than 0.3 percent.