Crave the Chameleon

It’s okay to Crave a Little Chameleon- 

These are the chemical structures of both CBD and THC:

Chemical structure of CBD
Chemical Structure of THC

Both are naturally occurring compounds, known as phytocannabinoids that interact with CB1 and CB2 receptors found in the endocannabinoid system of all mammals.
CB1 receptors are found throughout the body, but more concentrated throughout the central nervous system; while CB2 receptors are found in the immune and gastrointestinal systems.

Here is a great article by Jack Rudd from Analytical Cannabis. He discusses in more detail the chemical structure of CBD vs. THC, similarities and differences, history and properties of both.