Folio refers to the size of the book format, that is, how many pages are cut on a fully open printing paper. Common ones are 32 quarts (mostly used in general books), 16 quarts (mostly used in magazines) and 64 quarts (mostly used in small and medium-sized dictionaries and comics). Under the premise of not wasting paper and facilitating printing and binding production, how many open pages are cut into several small pages with equal area is called how many. Binding them into a book is called how many folio.