Soon, the days of tucking your boarding pass into your passport will be a distant memory. As more airlines move towards digital boarding passes – including Ryanair, which will ban paper boarding ...

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.

Whether it’s modern-day and digital or old-school and printed, a boarding pass is your golden ticket to adventure. But if you’re not careful, it could also become a one-way pass to trouble.

The pass will also contain all passport details. With no check-in, a passenger’s face will be scanned when they arrive at the airport, alerting the airline of their intention to fly.

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

The code "SSSS" on a boarding pass stands for "Secondary Security Screening Selection," requiring additional screening at TSA checkpoints. Reasons for the "SSSS" code can include last-minute ...

Boarding pass information can be used by anyone to alter your flight reservation. You should also avoid looking at sensitive information on public wifi networks when you travel.

This article originally appeared on Austin American-Statesman: Did TSA put 'SSSS' on your boarding pass? Here's what these four letters mean A TSA agent checks the ID of a traveler at Phoenix Sky ...

If you do find this quartet of letters on your boarding pass, allow 15–45 minutes of extra time to get through security at the airport. This story was updated to add a gallery.