The question as to why plane windows are round may not have crossed your mind while you stare out of one, what with all the clouds, sunrises/sets, building frost and general epicness of the planet.
Turns out there's a very good reason why the windows are oval rather than square, and it's not because planes are the ferries of the sky.
Back in the 50s, higher air travel started to take off. Pressurised cabins meant that planes could go higher and faster than before, and it was the beginning of flight as we know it.
But in 1953, two planes fell apart in the air, killing 56 people. And it came down to the rectangular windows.
Where there is a corner there is a weak spot, which can cause windows to collapse from things like changes in air pressure. That means each square or rectangular window on a plane had four opportunities to become an exit that they didn't mention in the safety video.
By being round, any stress to the windows is distributed and the risk of cracking reduced.
While we're at it, that tiny hole in them is there to maintain cabin pressure should the synthetic resin on the outside window pane fracture for any reason.
So you can go back to staring at the clouds, sunrises/sets and building frost with a god-like perspective without having to worry about the thing your pressing your face against exploding.