Kerosene, known as paraffin oil in the United Kingdom, is a flammable liquid obtained by distilling petroleum at a high temperature. Kerosene has been widely produced since 1846, although it didn't become popular as an useful element until a few years later, and only thanks to the work of several chemists in distant corners of the world. Kerosene Gaslight Company, founded in 1851, was the first company in the world to sell kerosene for both commercial and home use.

Kerosene is primarily used for heating and fueling vehicles. Up until electricity was invented, kerosene was the main source of lighting, as it was used widely in home lanterns. It is still used for that purpose by the Amish. Otherwise, kerosene is considered too dangerous to be used in enclosed areas, and its use as a lighting source is discouraged by many health agencies. Kerosene-based heaters, however, are popular in Asia, where kerosene is readily available, and in outdoor-supply stores, where kerosene is sold as an alternative fuel for camping stoves.

Kerosene is used as a primary source of fuel for many types of aircraft, including rockets, although in this case the kerosene is mixed with liquid oxygen in order to produce enough of a heating source. While there are no cars that can run on kerosene, many people use it to either extend the life of their gasoline or to keep gas from freezing during winter. It's important to note that kerosene is as volatile as gasoline, so it should be handled with care at all times.

Although kerosene is deadly if ingested, it has been used through history to treat a number of diseases. Folk medicine sees kerosene as a powerful antidote for snakebites, and is also often used to kill lice and prevent mosquito breeding. In underdeveloped countries with limited access to medicine, kerosene is often used as a replacement for alcohol to treat cuts and burns, stop bleeding, and against athlete foot and hemorrhoids.