Delta Air Lines is one of the most popular airlines in the world. The Atlanta, Georgia-based carrier is the largest airline in the world in terms of total passengers and number of departures. Alongside its regional subsidiaries and contractors operating under Delta Connection, the airline has over 5,000 daily flights. These flights fly to over 300 destinations in 50 countries. Delta is also the second-oldest operating commercial airline in the United States, trailing only United Airlines.