There is nothing better than getting the window seat on a flight - but what purpose do they really serve? They don't help the pilots or cabin crew at all and are actually a hinderance as they can cause serious safety issues.
A lot of time and effort has gone into making sure the design of the windows is perfect, which is why they're a peculiar round shape and have tiny holes in them. Yesterday, a passenger on a flight to New York has shown footage of the terrifying moment when a window on the plane cracked.
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A safety message was given out to the passengers by one of the crew to keep calm - with the airline later explaining that the tightness of the window was not damaged and it was the electrophotochromatic layer used to darken the glass which was affected.
So what actually is the point of having windows on a plane?
They are purely to improve the experience for passengers, so they don't feel claustrophobic in a giant metal tube.
Software engineer Shaunak Bhattacharjeee explained on Quora: "Aeroplanes are not designed by keeping the luxury or comfort of the passengers but their safety.
"The main purpose of having windows inside an aircraft is simply not to make the passengers feel claustrophobic.
"Otherwise, they serve no purpose but takes up more technology and money to construct them."
That explains why windows exist on planes, but why are they a round shape rather than the traditional rectangle we usually see?
They did used to be square but were changed after two devastating tragedies that happened in the 1950s.
In January 1954, a flight from Rome to London disintegrated in the sky and crashed into the Mediterranean Sea, killing all 35 passengers and crew on board.
Just months later, a South African Airways flight from London to Johannesburg crashed into the sea and the 21 dead pssangers had similar head and lung injuries to those on the other flight.
It transpired that the windows were a major factor in the metal fatigue that caused explosive decompression and the plane breaking up mid-air.
Because they were square in shape, the stress was concentrated in the four corners of the window.
Willis Orlando, Product Operations Specialist at Scott's Cheap Flights told The Sun : "Rounded corners are designed to help distribute the pressure exerted on the window evenly, reducing the likelihood of a window cracking under changing air pressure."
Designers decided that rounder windows would be far safer because the stress would flow more evenly around the edges of the window.
Having a tiny hole in your window might sound like a terrifying concept, but it's also there for a very important reason.
The Federal Aviation Administration (FAA) explained the hole is used to regulate air pressure and stop the cabin from decompressing.
As the plane gains altitude, the air pressure outside drops compared to the regulated air pressure inside the cabin, so the difference puts physical stress on the windows - made up of three panes of glass.
There's a small air gap in between the middle and outer panes and the hole is actually in the middle pane - and called a "breather" or "bleed hole".
The outer pane takes the pressure, whereas the middle pane acts as a fail-safe just in case that other one fails.
The hole also has another role though - releasing moisture from the gap preventing the little windows from fogging or frosting over.
Finally we get down to the blinds, which some of us like to close during the flight, but cabin crew always make you pull them back up for take off and landing.
There are two reasons for this, the first being to adjust passengers' eyes to the light outside in case of an emergency.
Airlines tend to aim to complete evacuations in 90 seconds, so having passengers who can easily see where they are going can be a major help.
This is also why the cabin lights are dimmed before plane landings at night time, but what's the second explanation?
Former pilot John Keese explained that it's useful in an emergency for people - whether that be cabin crew or passengers - to see what is going on outside the cabin.
With all of the window blinds up, in the event of an emergency it means that cabin crew can have a clearer picture of what is going on and assess the situation.
For example, in the rare case of an evacuation, they can check that the surroundings are safe before people disembark from the plane.
The extra benefit is that, with the plane windows raised, passengers can see out of the windows easily and can spot any potential issues.
Most of us are keen to get the coveted window seat because of the incredible views - and it's easy to lean against the side to go to sleep.
However, those in the know have warned that sleeping against the window can be a grim experience as certain parts of the plane are not as clean as others.
Last month, cabin crew member Tommy Cimato said: "Do not fall asleep or lean your head on the window."
Tommy warned that the window is best avoided because you can't be sure if it has been cleaned or not - and you don't know how many other people have rested their face against it.
“You are not the only one that has done that and you don't know how many people or children have wiped their hands or other things all over the window," he added
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