The standard was originally introduced into the DIN in 1922 by the German Empire (number DIN 476), although some of its format was developed at the same time in France, but later it was forgotten. ISO 216 defines the three sets of paper sizes A, B, and C. Group C paper sizes are mainly used in envelopes.
A4 paper larger than A5The A4 paper is by the international organization for standardization ISO 216 definitions, specifications for 21*29.7cm (210mm * 297mm), used by most countries in the world are using paper size of this international standard.
Printing industry paper specification: 148mm X 210mm (width X high). This is a very common specification. A5 paper, that is, A type of basic size of paper folded 5 times, so a piece of A5 paper area is 2 of the basic paper area of 5 times, that is, 1/32. A5 paper is A4 half, commonly known as the 32 paper.
