A4 paper is defined by ISO 2 16, and its specification is 21* 29.7 cm (210 mm× 297 mm). Most countries in the world use this international standard for paper size.
This standard was first incorporated into DIN (DIN 476) in 1922 by Weimar * * and China. Although some formats were developed in France at the same time, they were later forgotten.
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About the proportion of paper
/kloc-In the 20th century, some people without artistic prejudice conducted some experiments based on science. It is said that they have found an objective answer to what is the most beautiful proportion. This ratio formula is known as the golden ratio (1: 1.6 18).
Although as early as the Renaissance, those artists began to use the golden ratio to divide paintings, it was not until the19th century that people began to raise it to the stage of scientific theory to re-examine and study it.
The concept of beauty will have different changes in different periods. When the mode of mass production penetrated all over Europe in the early 20th century, the game between function and aesthetics began to appear on paper.
For paper, design pioneers believe that paper should not only have absolute practicality, but also have aesthetic feeling. At that time, the way to gain aesthetic feeling has changed from imitating natural organic forms to worshiping technology and industrialization.
In order to make paper both functional and aesthetic, they found an interesting combination between traditional aesthetics and emerging industrial aesthetics.
This combination point is-ratio.
Baidu encyclopedia -A4 paper