From their website:
AirTran Airways is one of America's largest low-fare airlines - employing more than 7,500 friendly, professional Crew Members and operating almost 700 flights a day to 50 destinations.
The airline's hub is at Hartsfield - Jackson Atlanta International Airport, the world's busiest airport by passenger volume, where it is the second largest carrier.
AirTran Airways, a subsidiary of AirTran Holdings (NYSE: AAI), is the world's largest operator of the Boeing 717 and has America's youngest all-Boeing fleet. The airline recently added the Boeing 737-700 aircraft, one of the most fuel efficient and environmentally friendly aircraft flying today, to its fleet.
More information available at Wikipedia.