| As New | The book is in the same condition as when it was published. There are no defects and the dust jacket, if there is one, is also perfect. |
| Fine | Not as crisp as "As New", but with no defects. Any damage to a dust jacket should be noted. |
| Very Good | A book showing wear, but with no tears to the binding or paper. Any defects should be noted. |
| Good | Average, with all pages and leaves present. Defects noted. |
| Fair | A worn book with complete text. It may be missing endpapers and half-title. These defects should be noted. |
| Poor | A book whose only merit is as a Reading Copy. |
| Ex-Library | Regardless of condition, this must be noted. |
| Folio | Approx. 15 inches high |
| Quarto (4to) | Approx. 12 inches high |
| Octavo (8vo) | Approx. 9.75 inches high |
| Duodecimo (12mo) | Approx. 7.75 inches high |
| Sixteenmo (16mo) | Approx. 6.75 inshes high |
| Twentyfourmo (24mo) | Approx. 5.75 inches high |
Book sizes were originally based on a sheet of paper that measured 19 by 25 inches. Sizes are based on the number of leaves created when the sheet was folded.