These are just IATA (International Air Transport Association) codes. They are used in aviation to identify and differentiate airports. That’s why a Richmond Byrd Intl Airport to San Francisco Airport flight would often be abbreviated as a RIC to SFO 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 Norfolk Airport (ORF), Newport News Intl Airport (PHF), Pitt-Greenville Airport (PGV).