Book formats

The traditional terms in use for describing book formats are derived from early printing methodology and the size of early handmade sheets of paper. When two leaves (four pages when printed on both sides) were printed on a sheet so that it could be folded once, collated with other folded sheets and bound, the format of the volume was a “folio”. When four leaves (eight pages) were printed on the same size sheet, which would later be folded twice, the format of the resultant volume was a “quarto” (four leaves). The term “octavo” relates to the sheet having eight leaves printed on it.