During our school days, most of us probably used jotters or exercise books that had margins running down each side, and probably never gave a second thought as to why they were there.
They were handy for writing numbers and bullet points when it came to answering questions, as they helped you keep track of what you'd done.
They also came in useful for teachers to mark your work or make any notes - but it turns out that none of these are the real reasons why margins were introduced in the first place.
The Mirror reports that a person on Reddit sparked a conversation on the topic, asking: "In school, whenever writing in an exercise book we were always told to draw a margin on our page. But why? What is the purpose of a margin? Do kids still write in exercise books? Do they still draw margins?"
According to My Reading World, margins were introduced to prevent rats and mice from chewing through paper as they frequently found their way into libraries.
A statement reads: "In the past, where everything was dealt with papers, be it important records, confidential documents, or perhaps agreements, it was all stacked up in paper records and stored in a relatively protected place.
"But the real dangers of lost information wasn’t from humans but rats and mice. These tiny rodents love the taste of paper and are prone to eating away the documents, especially from the edges.
"Therefore, the manufacturers added margins on the edges of the notebooks so, despite any rodent intrusion, you can rest assured that your notes are safe at all times."
However, they also have other important functions which is why they've stuck around for so long.
For example, they help to keep any notes concise and easy to read, as well as providing a space to correct any mistakes without cluttering the page.
The statement from My Reading World continued: "Another way this can be used is for teachers. Teachers can easily give student notes, grades, and remarks on the margins without altering the students’ writing.
"Besides that, imagine a page without the top margin. Ever wondered how are you going to write the heading?
"Wouldn’t that look too cluttered if you mix in the title with the body text? In these cases, margins help keep your work organized by allocating a separate space for items relevant to the page but need to be written separately.
"It can also be used to write the key if you’re using any colour codes for the page."
In the Reddit post's comments, people were quick to offer the same explanation, with one person saying: "Rats used to nibble at the edges of paper in libraries and studies hundreds of years ago, and it was a way to protect the writings from them."
But someone else said they were created because of another pest guilty of eating paper, writing: "The original margins in books were based on how far bookworms ate into a book. Of course it's not perfect but it did save a lot of the writing."
And a third user alternatively suggested: "The margin is so you don't write too close to the edge of the book, where your hand might bump the edge and make your already scribbley handwriting worse. Books are less common, as worksheets are cheaper."
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