These are just IATA (International Air Transport Association) codes. They are used in aviation to identify and differentiate airports. That’s why a Miami Airport to San Juan Luis Munoz Marin Intl Airport flight would often be abbreviated as a MIA to SJU flight. This flight route has multiple associated airports, so we think it might be helpful to learn the name and codes of them as well. They are Punta Cana Airport (PUJ), Santo Domingo Las Americas Airport (SDQ), Montego Bay Sangster Intl Airport (MBJ), Oranjestad Reina Beatrix Airport (AUA), Santiago de los Caballeros Airport (STI).