When items are graded in the electronics field it normally is in the plastics and LCD of the notebook computer.  Each notebook computer or part can fall into 3 catagories.

New, Refurbished, or Used

New is considered to have never been in a unit and free of blemishes.

Refurbished means that the item has been inspected and tested for full functionality and falls into the 3 cosmetic Grades A, B, C.

Used means that the part has been in a unit.  Functionality should be stated for the item.  They can also be Graded A, B, C.

Grading

Grade A  - Like new condition

Grade B - Minor blemishes, normally very small in nature.

Grade C - Heavy wear, noticable scratches