Brand New - New, unread, unused, and in perfect condition with no missing or damaged pages.

Like New - Shiny, undamaged cover, no missing pages, all pages undamaged, no underlining/highlighting, no damage to binding, no writing in margins.

Very Good - Doesn't look brand new but has no easily noticeable damage to the cover, no missing pages, all pages undamaged, no underlining/highlighting, no writing in margins, very minimal identifying marks inside cover, very minimal wear and tear ( You would give to a  good friend as a gift)

Good - Very minimal damage to the cover, minimal wear to binding, majority of pages undamaged, minimal pencil underlining of text, no missing pages ( You would use it yourself, but wouldn't necessarily give it as a gift)

Acceptable - Some damage to the cover but integrity still intact, binding slightly damaged but integrity still intact, possible writing in margins, possible underlining and highlighting of text, no missing pages (Book beaten up a bit but it works)

This is how we try to rate our books. However, be sure to read each description carefully. Some books may have special cases. If you have any questions about this, please ask. Also all books are ex-school copies.