The condition of each stamp/cover is noted as follows:
Mint: Stamp - unused and in as new condition. Cover - in as new condition.
Fine: Stamp - used/unused Stamp and/or cover - not easily bettered.
Very good (VG): clean stamp with minor imperfections/slightly heavier cancellation/hinge residue. Cover will have minor imperfections/marks. Imperfections will be evident from picture or will be stated.
Good (G): Stamp may have heavy cancellation, minor creasing, small patches of staining, slight damage to back. Cover will have small creases/marks/imperfections. Imperfections will be evident from picture or will be stated.
Damaged: damage will be evident from picture or will be stated.
Unused - no cancellation
Unmounted - no sign of hinge marks
On paper - stamp is still on paper/card
Cover - stamp is on envelope or postcard
First Day Cover (FDC) - special cover postmarked on the first day of issue
There is some overlap between these terms e.g. a stamp described as mint is also unused and unmounted