What Happened To US Low-Cost Carrier AirTran Airways?

AirTran Airways, or simply AirTran, was a US budget carrier with its head office based in Florida and its main hub in Atlanta. Operating mainly Boeing 717s and 737s, the airline would shuttle passengers around the US Midwest and East Coast. Operating for 21 years, AirTran ceased operations in 2014. Why doesn’t the airline still exist today?