Delta Air Lines, Inc. is a major airline based in the United States headquartered in Atlanta. Delta is the world's largest airline operating under a single certificate, operating flights on six continents across the globe. Delta operates an extensive domestic and international network, spanning North America, South America, Europe, Asia, Africa, the Middle East, the Caribbean and Australia. Delta and its subsidiary Delta Connection operate over 4,000 flights every day. Delta and the Delta Connection carriers fly to 348 destinations in 64 countries. (excluding codeshare) Delta operates the world's largest and busiest hub atHartsfield-Jackson Atlanta International Airport. It has been the world's busiest airport by passenger traffic and number of landings and take-offs since 1999, serving 88 million passengers per year. Delta is a founding member of the SkyTeam alliance.
On October 29, 2008, Delta completed its merger with Northwest Airlines to form the world's largest commercial carrier. In February 2009, the airline began consolidating gates and ticket counters at airports where both Delta and Northwest operate. The consolidation was completed February 2010. On December 31, 2009, the Federal Aviation Administration granted Delta's request to allow Delta and Northwest to operate under a single operating certificate.