Petroleum = petra, Greek = rock, and oleum, Latin = oil.
So we have an oil from rock. And by common usage, all substances deriving from it.
Petroleum
Petroleum is refined from crude oil and is but one fraction only
crude oil is a petroleum
"Petroleum" products are distilled from crude oil, so what comes out of the ground is crude oil.
No, not actually. Crude oil is one type of petroleum. Petroleum is a common term for the liquid (crude oil), gaseous (natural gas), and viscous or solid forms (bitumen and asphalt).
crude oil
Probably, if not they are REALLY close. I hope that helped some. :D
Petroleum is a crude oil that is used to produce gasoline.
crude oil
You don't crack Petroleum. Petroleum is one of the distillates of cracking crude oil.
Crude oil is processed to obtain petroleum products.
You may be thinking of petroleum.