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Commercial production of oil is considered to have started in 1859 in the United States with the discovery of oil near Titusville, western Pennsylvania, by "Colonel" [http://www.portal.state.pa.us/portal/server.pt/community/people/4277/drake,_edwin_l_/443544 Edwin L. Drake]. Several countries soon joined the United States as oil producers, and by the turn of the century, the world's production had reached 350 million bbl per year. Production of oil reached 1 billion bbl in 1923, 2 billion bbl in 1939, and 3 billion bbl in 1947. Production grew at an increasing rate in the following decades, reaching 20.3 billion bbl annually in 1973. The rapid increase in production that characterized the 1950s, 1960s, and early 1970s was interrupted in 1973 by the [https://en.wikipedia.org/wiki/1973_oil_crisis first oil shock], the consequence of the Yom Kippur War, and the resulting Arab oil embargo, which brought a sharp increase in the price of oil. Annual oil production dropped sharply to 19.3 billion bbl.

Commercial production of oil is considered to have started in 1859 in the United States with the discovery of oil near Titusville, western Pennsylvania, by "Colonel" [http://www.portal.state.pa.us/portal/server.pt/community/people/4277/drake,_edwin_l_/443544 Edwin L. Drake]. Several countries soon joined the United States as oil producers, and by the turn of the century, the world's production had reached 350 million bbl per year. Production of oil reached 1 billion bbl in 1923, 2 billion bbl in 1939, and 3 billion bbl in 1947. Production grew at an increasing rate in the following decades, reaching 20.3 billion bbl annually in 1973. The rapid increase in production that characterized the 1950s, 1960s, and early 1970s was interrupted in 1973 by the [https://en.wikipedia.org/wiki/1973_oil_crisis first oil shock], the consequence of the Yom Kippur War, and the resulting Arab oil embargo, which brought a sharp increase in the price of oil. Annual oil production dropped sharply to 19.3 billion bbl.

After 1975, annual oil production resumed its increase until 1979, when it reached 22.8 billion bbl. The Iranian Revolution brought the [https://en.wikipedia.org/wiki/1979_energy_crisis second oil shock]; oil exports from Iran ceased, the price of oil increased drastically, and world oil production declined during the next 4 years to about 19.3 billion bbl in 1983. Production increased slowly afterward to about 22 billion bbl in 1990 and remained at that level until 1994. Production has increased slowly since 1994 to close to 25 billion bbl per year. This more stable production of oil has been attributed to higher prices, more efficient use of energy, a comeback of coal, the entry of nuclear power, and particularly, [[Natural-gas liquids|natural gas]] in the generation of electricity and to the realization by the governments of many industrial countries that, for security reasons, it is dangerous to depend too heavily on a single source of inergy.  

After 1975, annual oil production resumed its increase until 1979, when it reached 22.8 billion bbl. The Iranian Revolution brought the [https://en.wikipedia.org/wiki/1979_energy_crisis second oil shock]; oil exports from Iran ceased, the price of oil increased drastically, and world oil production declined during the next 4 years to about 19.3 billion bbl in 1983. Production increased slowly afterward to about 22 billion bbl in 1990 and remained at that level until 1994. Production has increased slowly since 1994 to close to 25 billion bbl per year. This more stable production of oil has been attributed to higher prices, more efficient use of energy, a comeback of coal, the entry of [[nuclear power]], and particularly, [[Natural-gas liquids|natural gas]] in the generation of electricity and to the realization by the governments of many industrial countries that, for security reasons, it is dangerous to depend too heavily on a single source of energy.  

A detailed and extremely interesting history of the oil industry can be found in Daniel Yergin's [http://books.google.com/books/about/The_Prize.html?id=WiUTwBTux2oC The Prize: The Epic Quest for Oil, Money and Power].

A detailed and extremely interesting history of the oil industry can be found in Daniel Yergin's [http://books.google.com/books/about/The_Prize.html?id=WiUTwBTux2oC The Prize: The Epic Quest for Oil, Money and Power].