Standby
Standby refers to a situation in which an air passenger is waiting for, but has not secured, seats on the next available flight or an upgrade to a higher cabin class. Standby can result when a ticketed passenger wishes to fly earlier or later the same day, has missed a flight, or had a previous flight cancelled or delayed. Passengers who request an upgrade are also placed on a standby list. Airline employees also have access to discounted tickets that allow them, their friends and family to fly standby on a seats-available basis.