+Petroleum is a naturally occurring, dark, viscous liquid, often called [Oil](/wiki/Oil), formed from ancient organic matter deep within the Earth. This [Fossil Fuel](/wiki/Fossil_Fuel) is a vital global energy source and the raw material for countless modern products.
+## See also
+- [Energy](/wiki/Energy)
+- [Fuel](/wiki/Fuel)
+- [Hydrocarbon](/wiki/Hydrocarbon)
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