is petroleum oil
petroleum, rock oil (mid-14c. in Anglo-French), from Medieval Latin petroleum, from Latin: petra : rock + oleum : oil. ) is a naturally occurring, yellow-to-black liquid found in geological formations beneath the Earth 's surface, which is commonly refined into various types of fuels.he use of fossil fuels, such as petroleum, has a negative impact on Earth's biosphere, damaging ecosystems through events such as oil spills and releasing a range of pollutants into the air including ground-level ozone and sulfur dioxide from sulfur impurities in fossil fuels.