How did paper size come to be 8.5" by 11"?
It kind of seems like an arbitrary number. The world might be simpler if paper was square by default.
The standard paper size of 8.5" by 11" is called Letter size. It is commonly used in North America, while other regions like Europe and most other countries use the A4 paper size, which measures 8.27" by 11.69". The origins of the 8.5" by 11" paper size can be traced back to the traditional British paper sizes used in the 18th century.
The British paper sizing system employed a ratio of 1:√2 (approximately 1:1.414) for their paper sizes. This means that when a larger sheet of paper is divided into two equal halves, the resulting pieces retain the same proportions. This aspect of the British system made it easy to scale documents and drawings without distorting their dimensions.
In 1921, the American National Standards Institute (ANSI) adopted a series of paper sizes based on the British system. They standardized the paper size known as "Letter" to be 8.5" by 11". This particular size was chosen for its practicality—it provided a good balance between portrait and landscape orientation, as well as ample space for text and graphics.
Regarding your suggestion of having square paper as the default size, it might seem simpler at first glance. However, square paper does not fit well with the majority of printed content, which is typically designed for rectangular formats. Additionally, rectangular paper allows for greater versatility in terms of folding, binding, and organizing documents.
In conclusion, the 8.5" by 11" paper size became the default choice for Letter size in North America due to its adoption from the British paper sizing system and its practicality for various purposes. Different regions have their own standard sizes, but the goal is to find a balance between functionality and compatibility with different types of content.