In case you were wondering: Cannabidiol (INN;[3] abbreviated as: CBD) is one of at least 113 active cannabinoids identified in cannabis.[4][5] It is a major phytocannabinoid, accounting for up to 40% of the plant's extract.

https://en.wikipedia.org/wiki/Cannabidiol

It’s worth noting that a legal version, extracted from Hemp (a form of Cannabis that has no psychoactive properties), is available via mail order anywhere in the U.S.

I've wondered about the efficacy of the hemp versions. A friend of mine was using CBD oil to alleviate his daughter's seizures, and had told me that the hemp based ones were ineffective, and that THC in a small dose had a complementary effect.

I'm not sure if that applies to everything CBD is good for, but does anyone know if it works mostly the same for body aches and the like?

I’ve tried both (for migraines) and didn’t notice much of a difference.

I looked into the hemp based extract a while back and the conclusion I drew was that it was up for debate whether or not it was legal. Proponents cited a bunch of laws regarding industrial hemp while the DEA seemed to have another position entirely. Was this finally settled or is it still a bit gray?

Since vitamins and supplements are totally unregulated it could be that it doesn't actually contain any of the active ingredient it claims it does, thereby avoiding any legal issue.

i've heard of a cbd extract from hops, but i'm not sure whether it's true.

Hemp is not "a form of" cannabis. It IS cannabis.

Sorry...I should have said “variety” instead of “form.”