Here is the standard Planetary Sounds uses when it comes to grading records and covers.
Remember, even with such a guide, grading is still subjective. Most albums, unless noted, are visually graded under bright lights. We strive to provide as much information as possible about each album. Please ask questions if unsure about anything BEFORE you buy.
Still Sealed (SS) As good as it gets. Unopened and most likely perfect all around.
Mint (M) Absolutely perfect in every way. Maybe played once. Handled with utmost care. Grade used only on rare occasions.
Near Mint (NM or M-) A nearly perfect record. The record shows no obvious signs of wear. Covers show no more than the most minor defects. The same holds true for inserts, such as posters, lyric sleeves, etc.
Near Mint Minus or Very Good Plus Plus (NM- or VG++) Just a hair more wear than NM, but still very close to Near Mint overall. Vinyl may have nominal sleeve or paper scuffs, cover may have hint of wear. VG++ will be just a fraction below NM- due to one additional tiny defect.
Very Good Plus (VG+) Album and cover show some light signs that it was played and otherwise handled with care of it. Record surfaces may have slight surface scuffs or very light scratches that don't affect play. If not for a couple things wrong with it, this would be Near Mint. Covers may have some cornerwear, edgewear or ringwear, maybe a combination of the above.
Very Good (VG) Increased scuffs or light scratches, surface noise evident upon playing. Covers and labels may have characteristics of the VG+ cover rating, but also be marred by writing, or have tape or stickers, or minor seam splits.
Very Good Minus (VG-) Certain background noise, possible click or pop, flawed item. Covers heavily damaged, major splits, tears, writing, etc.
Good (G) Not good at all. Heavy wear all around. Most would never be sold or played, but are only available due rarity.