ExxonMobil, is an American multinational oil and gas corporation. It is a direct descendant of John D. Rockefeller’s Standard Oil company, and was formed on November 30, 1999, by the merger of Exxon and Mobil. Its headquarters are in Irving, Texas. It is affiliated with Imperial Oil which operates in Canada. ExxonMobil is one of the largest publicly traded companies by market capitalization in the world, having been ranked either No. 1 or No. 2 for the past 5 years, and is the second largest company in the world by market revenue.
Exxon Mobil’s reserves were 72 billion oil-equivalent barrels at the end of 2007 and, at then (2007) rates of production, are expected to last over 14 years.  With 37 oil refineries in 21 countries constituting a combined daily refining capacity of 6. 3 million barrels (1,000,000 m3), Exxon Mobil is the largest refiner in the world, a title that was also associated with Standard Oil since its incorporation in 1870.  ExxonMobil is the largest of the six oil supermajors with daily production of 3. 21 million BOE (barrels of oil equivalent). In 2008, this was approximately 3% of world production, which is less than several of the largest state-owned petroleum companies.  When ranked by oil and gas reserves it is 14th in the world with less than 1% of the total.
The Exxon Mobil Corporation headquarters is located in Irving, Texas.
ExxonMobil markets products around the world under the brands of Exxon, Mobil, and Esso. It also owns hundreds of smaller subsidiaries such as Imperial Oil Limited (69. % ownership) in Canada, and SeaRiver Maritime, a petroleum shipping company. The upstream division dominates the company’s cashflow, accounting for approximately 70% of revenue. The company employs over 82,000 people worldwide, as indicated in ExxonMobil’s 2006 Corporate Citizen Report, with approximately 4,000 employees in its Fairfax downstream headquarters and 27,000 people in its Houston upstream headquarters. Operating divisions ExxonMobil is organized functionally into a number of global operating divisions. Read about ExxonMobil functional structure
These divisions are grouped into three categories for reference purposes, though the company also has several ancillary divisions, such as Coal & Minerals, which are stand alone. Chart of the major energy companies dubbed “Big Oil”, sorted by latest published revenue Upstream (oil exploration, extraction, shipping, and wholesale operations) based in Houston, Texas Downstream (marketing, refining, and retail operations) based in Fairfax, Virginia Chemical division based in Houston, Texas.