Peter Greenberg lays out what you need to know before booking your next flight

PHOTO: Inside the gate hall area of Terminal 1, waiting rooms, gates, seats, toilets, shops, duty-free, lounges with glass windows, chairs and airplanes at JFK / KJFK John F. Kennedy International Airport in New York City, USA. JFK is one of the biggest airports in the world with 4 runways and 8 terminals, the busiest international air passenger gateway in US. NY, United States of America (Photo by Nicolas Economou/NurPhoto via Getty Images)