BP p.l.c. is a British multinational oil and gas company headquartered in London, United Kingdom. It is the third-largest energy company and fourth-largest company in the world measured by 2011 revenues and one of the six oil and gas “supermajors”.  It is vertically integrated and is active in every area of the oil and gas industry, including exploration and production, refining, distribution and marketing, petrochemicals, power generation andtrading. It also has major renewable energy activities, including in biofuels, hydrogen, and wind power.

BP has operations in over 80 countries, produces around 3.8 million barrels of oil equivalent per day and has 22,400 service stations worldwide.  Its largest division is BP America, which is the biggest producer of oil and gas in the United States and is headquartered in Houston, Texas.  As at 31 December 2010 BP had total proven commercial reserves of 18.07 billion barrels of oil equivalent.  The name “BP” derives from the initials of one of the company’s former legal names, British Petroleum.

Info gleaned from Wikipedia