The letter and number codes on a boarding pass tell a lot about you, including whether you've been chosen for extra screening ...

These are some of the most common codes seen on airline boarding passes: SSSS: ... It indicates the passenger's ticket is for a full-price business class fare. Y: Economy Class.

But your boarding pass contains a lot more than just your plane seat and gate number. It also includes codes that communicate details about passengers and their itineraries to airport staff.

Boarding passes may just seem like a piece ... place in boarding and letters used to identify a passenger's fare class. ... of the most common codes seen on airline boarding passes: ...