Folio

The term "folio" (from Latin folium 'leaf') has three interconnected but distinct meanings in the world of books and printing: first, it is a term for a common method of arranging sheets of paper into book form, folding the sheet only once, and a term for a book made in this way; second, it is a general term for a sheet, leaf or page in (especially) manuscripts and old books; and third, it is an approximate term for the size of a book, and for a book of this size. First, a folio (abbreviated fo or 2o) is a book or pamphlet made up of one or more full sheets of paper, on each of which four pages of text are printed, two on each side; each sheet is then folded once to produce two leaves. Each leaf of a folio book thus is one half the size of the original sheet. Ordinarily, additional printed folio sheets would be inserted inside one another to form a group or "gathering" of leaves prior to binding the book. Second, folio is used in terms of page numbering for some books and most manuscripts that are bound but without page numbers as an equivalent of "page" (both sides), "sheet" or "leaf", using "recto" and "verso" to designate the first and second sides, and (unlike the usage in printing) disregarding whether the leaf concerned is actually physically still joined with another leaf. This usually appears abbreviated: "f26r." means the first side of the 26th leaf in a book. This will be on the right hand side of the opening of any book composed in a script that is read from left to right, such as Latin (as used in English), Cyrillic, or Greek, and will be opposite for books composed in a script that...