CBG cannabigerol

CBG is the result of CBGA going through decarboxylation. Like CBGA, CBG is rarely found in cannabis extracts because its acidic precursor is converted to other cannabinoids by enzymes in the plant before it can be extracted and decarboxylated.

CBC cannabichromene

CBC is one of the 3 primary cannabinoids of the cannabis plant. When CBGA, the root cannabinoid and precursor to all other cannabinoids, is created by the cannabis plant, enzymes in the plant will convert the CBGA into one of 3 major cannabinoid

Terpenes, or Terpenoids

One thing many people notice about cannabis is the smell, which varies a lot from strain to strain. Contrary to popular belief the cannabinoids in cannabis, like THC, have no smell and the unique fragrance of various cannabis strains is actually 

CBN cannabinol

CBN is essentially degraded THC. Just as decarboxylation converts THCA to THC, by removing the Co2 molecule, THC will then oxidise or degrade to CBN, as it loses its hydrogen component. Both decarboxylation and oxidisation occur 

THCV tetrahydrocannabivarin

THCV is different from THC (and other well known cannabinoids, like CBD, CBC, CBN etc.) in the sense that it does not actually come from CBGA.
The cannabis plant combines geranyl pyrophosphate