You may have noticed that some plane seats are different from others if you’re a frequent traveler or simply a perceptive person.

You may have secured a seat by the window, only to see a tiny black triangle over it.

One flight attendant has revealed the symbol’s hidden meaning, but it’s one of those things we usually just accept without ever understanding.

A member of the cabin crew for Cebu Pacific, an airline based in the Philippines, has disclosed the “secrets” of airplanes and the meaning of the black triangle.

Henny Joyce Lim shared a video with little-known facts on her @_hennylim_ TikTok profile.

In the clip, she said, “Number one. Passengers sitting next to the triangles get the best view of the wings.”

“If flight crew need to check the wings, these triangles let them know the best vantage points for the slats and flaps outside.”

“If you are flying an airline that allows you to choose your own seat, look for one of the triangles in the cabin. Anybody who loves taking window shots or videos will get the best view of the wings from these seats.”

Lim went on to explain that “those triangle-marked seats are either at number 10 or at 18, but it still depends on the type of aircraft one is traveling in”.

As the movie came to a close, the flight attendant wished everyone a safe journey.

Many individuals were shocked by this revelation, and many expressed their feelings in the comment area.

One user asked, “When there is no seat available, can you sit anywhere? Or when checking in, do they give you a seat like that?”

Lim replied, saying, “Aircraft transferring on seats is not allowed unless authorized by cabin crew.”

Another person posted, “I’m always in the window seat near the wings, same as in the video, but I don’t notice the triangle.”

A third wrote, “Who wants to get the best view of the wings? Definitely not me.”

A fourth user added, “Also mainly used for break in points, right?”

Lim responded with, “Yes, correct also.”

Another member of the cabin crew revealed why airplanes are always so cold, so the TikToker isn’t the first flight attendant to reveal some of the mysteries of aircraft.

Jay Robert, a senior international cabin crew member and creator of A Fly Guy’s Cabin Crew Lounge, said: “We know it’s cold … but we also know what happens when the cabin is too warm, and that is a lot harder to manage than a cold cabin.”

“I used to work on the largest commercial aircraft in the world that seated over 600 passengers, and one of the things I regularly checked was that the temperature did not exceed 73 degrees (Fahrenheit).

“Sometimes, I would have two or three faintings on a flight, and I would call the front to check the temperature — it was 75 (Fahrenheit) or higher every time.”