Crude oil is a naturally occurring, unrefined petroleum product composed of hydrocarbon deposits and other organic materials. It is a type of fossil fuel, which can be refined to produce petroleum products such as petrol, diesel, kerosene, ATF and various forms of petrochemicals.
Crude oil is typically obtained through drilling, where it is usually found alongside other resources, such as natural gas (which is lighter, and therefore sits above the crude oil) and saline water (which is denser and sinks below). It is then refined and processed into a variety of forms, such as gasoline, kerosene and asphalt, and sold to consumers. Crude oil has a wide-ranging viscosity and can vary in color from black and yellow depending on its hydrocarbon composition.