Exxon, Gulf, Texaco, Mobil, Socal, B.P., and Shell: five huge American companies, one British company, and one Anglo-Dutch concern have dominated the world of oil - as oil has dominated all of us - for most of the century since the first Pennsylvania strike. How did this largest and most critical of the world's industries come under the control of these seven giants, and what will happen to them now, balanced on the tightrope between the demands of consumers and their partnership with the producing countries of OPEC?