Oi or OI may refer to:
An oil tanker, also known as a petroleum tanker, is a merchant ship designed for the bulk transport of oil.
An oil platform, offshore platform, or (colloquially) oil rig is a large structure with facilities to drill wells (optionally), to extract and process oil and natural gas, or to temporarily store product until it can be brought to shore for refining and marketing.
Oil sands, or more technically bituminous sands, are a type of unconventional petroleum deposit. Oil sands are either loose sands or partially consolidated sandstone containing a naturally occurring mixture of sand, clay, and water, saturated with a dense and extremely viscous form of petroleum technically referred to as bitumen (or colloquially as tar due to its superficially similar appearance).
An oil spill is the release of a liquid petroleum hydrocarbon into the environment, especially marine areas, due to human activity, and is a form of pollution.
The Oil-for-Food Programme (OIP), established by the United Nations in 1995 (under UN Security Council Resolution 986) was established to allow Iraq to sell oil on the world market in exchange for food, medicine, and other humanitarian needs for ordinary Iraqi citizens without allowing Iraq to boost its military capabilities.
An oil refinery or petroleum refinery is an industrial process plant where crude oil is processed and refined into more useful products such as petroleum naphtha, gasoline, diesel fuel, asphalt base, heating oil, kerosene, and liquefied petroleum gas.
Oil reserves denote the amount of oil that can be technically recovered at a cost that is financially feasible at the present price of oil.
An oil lamp is an object used to produce light continuously for a period of time using an oil-based fuel source.
An oil well is a boring in the Earth that is designed to bring petroleum oil hydrocarbons to the surface.