According to the size, folio is usually divided into three types: large format, medium format and small format. For 787× 1092 paper, 12 format is large format, 16 ~ 36 format is medium format, and 40 format is small format, but books with mainly characters are generally medium format.
Folio shapes are rectangles with different proportions except 6 quarts, 12 quarts, 20 quarts, 24 quarts and 40 quarts, which are suitable for books with different properties and uses.
Extended data:
According to the basic area of paper format, the format specifications are divided into A series, B series and C series. The folio size of A0 is 841mm×1189mm, and the folio area is 1m2. The width of B0 is1000 mm×1414 mm; The width dimension of C0 is 9 17mm× 1297mm, and the width area is1.2m2;
The format specification of copy paper only adopts A series and B series. If A0 paper is split in half along the length direction, it becomes A 1 specification; If A 1 paper is split along the length direction, it becomes A2 specification, and so on, it becomes A8 specification; B0 paper is also divided into B8 standard according to this method. The format sizes of A0 ~ A8 and B0 ~ B8 are shown in the following table. Among them, A3, A4, A5, A6, B4, B5 and B6 are common specifications of copy paper.