Delta Air Lines, Inc. is a major American airline, headquartered in Atlanta, Georgia. The airline operates an extensive domestic and international network serving six continents. Delta Air Lines and its subsidiaries operate over 5,000 flights every day and have approximately 80,000 employees. Delta is the sixth-oldest operating airline by foundation date, and the oldest airline still operating in the United States. Delta Air Lines is one of the four founding members of the SkyTeam airline alliance, the other three being Korean Air, Air France, and Aeroméxico. Regional service for the airline is served by Delta Connection.