These are just IATA (International Air Transport Association) codes. They are used in aviation to identify and differentiate airports. That’s why a Puerto Princesa Airport to Jeddah King Abdulaziz Intl Airport flight would often be abbreviated as a PPS to JED flight. Riyadh King Khaled Intl Airport (RUH), Medina Mohammad Abdulaziz Airport (MED), Dammam King Fahad Intl Airport (DMM), Tabuk Airport (TUU), Gassim Airport (ELQ) are other airports near this flight route and their unique identifiers/IATA codes. Find deals