THC is what's responsible for the psychoactive effects of cannabis—in other words, what makes you feel "high." CBD oil generally doesn't have THC, although trace amounts might be in products sold in certain states.

CBD oil contains CBD mixed with a like coconut oil or hemp seed oil. The bottled CBD oil is called a tincture and is sold in different concentrations https://coworkingmag.com/magazine/what-are-the-benefits-of-delta-8-thc-oil/.