CBG is Cannabigerol, the precursor to all other cannabinoids in the cannabis plant, so it's earned the name "mother of all cannabinoids". The CBG molecule is most prevalent when a cannabis plant is immature, and transforms to other cannabinoids like

They're both classified as a cannabinoid which is a compound found in cannabis. CBD (cannabidiol) has less affinity for CB1 and CB2 receptors. CBG binds more directly to CB1 and CB2 and therefore could create more endocannabinoid stimulation than CBD.