why notebook comes in rectangular shape?

WHY NOTEBOOK COMES IN RECTANGULAR SHAPE? 

There are various reasons that proves why notebooks always comes in rectangular shape -

1. Suppose, if we replace rectangular notebooks with square shaped notebooks, then 2 things can happen - whether the books will be too small or they will be too long, because all sides of the square are equal in length.

source- www.papergrid.in

2. It is difficult to write in a square shaped notebook, as the writer has to stretch his/her hand to the very end of the line of notebook. Another reason is that, while reading, the reader has to move his/her eyeballs to read the full line, which can reasult in eye strain.

source- 123rf.com

3. Now, if we replace rectangular notebooks with another shaped notebook then what will happen? -

A. If we replace it with triangular notebook -

If you will search "triangular notebook" in any e-commerce site, then you will find it costly as compared to the rectangular one.

source- shopify.com

B. If we replace it with circular one -

Same reason, it will be costly, but apart from this, it will also cause difficulty in writing and reading, because the width of the upper portion and middle portion of the notebook will not be same.

source- amazon.in

C. If we replace it with any other shape -

Same problems will be faced as mentioned above, if we replace it with any other shaped notebook. So, in my opinion, Rectangular notebooks are the best.