We did a recent HelloMD Live News segment where this question was addressed. The word cannabis is actually confusing because it is an umbrella term that encompasses hemp as well as medical cannabis aka ‘marijuana’.
It is classified as cannabis that has 0.3% THC or trace amounts and has much more CBD. Hemp was specifically bred for alternative reasons, other than medicine. Only products made from industrial hemp are legal to sell without a medical marijuana recommendation. Hemp is a legal crop in China, parts of Europe and Canada.
It has over 60 cannabinoids including THC and CBD. Some people believe the ‘entourage effect’, where multiple cannabinoids work together, creates a better medicine than hemp. (However, these days, hemp is now being bred to have very high levels of whole-plant CBD.) Due to marijuana’s THC content and the ability for people to get ‘high’, it has gained its notoriety which caused it to become illegal.
Both are considered schedule 1 drugs in the US. interestingly.