Like New: An apparently unread copy in perfect condition. Dust cover is intact, with no nicks or tears. Spine has no signs of creasing. Pages are clean and are not marred by notes or folds of any kind. Book may contain a remainder mark on an outside edge but this should be noted in listing comments.
Very Good: A copy that has been read, but remains in excellent condition. Pages and dust cover are intact and are not marred by notes or highlighting. The spine remains undamaged.
Good: A copy that has been read, but remains in clean condition. All pages are intact, and the cover is intact (including dust cover, if applicable). The spine may show signs of wear. Pages can include limited notes and highlighting, and the copy can include "From the library of" labels.
Acceptable: A readable copy. All pages are intact, and the cover is intact (the dust cover may be missing). Pages can include considerable notes--in pen or highlighter--but the notes cannot obscure the text.