NM (= M-): Near Mint: album has been played with no visible signs of wear or damage.
VG++ (= EX): Still very shiny, album has light signs of wear: a couple of inaudible light scuffs and/or light scratches.
VG+ : Some more wear, light scratches and/or scuffs: album plays with minimal surfacenoise = occasional light crackle, but still very enjoyable.
VG : Scratches and scuffs. Album plays with some more surfacenoise (light crackle and/or or occasional pops, but no skipped or repeat grooves).
G : Moderate, even wear throughout, still playable but with quite some surfacenoise (I rarely list records with this grade, except when they are very collectable