Editor's note: The New York Times reports that United's CEO Jeff Smisek resignation is tied to a federal corruption probe. United, the Times says, is under investigation 'over whether it had improperly sought to influence senior officials at the Port Authority of New York and New Jersey.' - Tom
United Airlines, Inc., commonly referred to as "United", is a major American airline headquartered in Chicago, Illinois. It is the world's largest airline when measured by number of destinations served. United operates a comprehensive domestic and international route network, and has significant presence in the Asia-Pacific region. In the late 1920s, just prior to the use of the United Airlines name, The Boeing Company, currently one of the world's largest aircraft manufacturers, operated a predecessor airline.
United is a founding member of Star Alliance, the world's first and largest global airline alliance. Regional service is operated by independent carriers under the brand name United Express. Its main competitors are American Airlines, Delta Air Lines, and Southwest Airlines.
United operates out of nine airline hubs located in Houston, Chicago, Newark/New York, Denver, San Francisco, Washington, D.C., Los Angeles, Guam, and Tokyo. George Bush Intercontinental Airport in Houston is United's largest passenger carrying hub handling 16.6 million passengers annually with an average of 45,413 passengers daily, while Chicago-O'Hare is its largest hub in terms of daily departures. The company employs over 88,500 people while maintaining its headquarters in Chicago's Willis Tower (formerly known as Sears Tower). Through the airline's parent company, United Continental Holdings, it is publicly traded under NYSE: UAL with a market capitalization of over $18 billion as of September, 2014.