The endocannabinoid system is part of the human body and made up of:
1) Cannabinoid receptor proteins that are positioned along the spine and nerves of the body.
2) Cannabinoids that are naturally produced within the body.
The above definition is a simplified version of the following endocannabinoid system definition:
The endocannabinoid system is a biological system composed of endocannabinoids, which are endogenous lipid-based retrograde neurotransmitters that bind to cannabinoid receptors, and cannabinoid receptor proteins that are expressed throughout the vertebrate central nervous system and peripheral nervous system.