Mint (M): Perfect, unplayed (almost never used for opened records).
Near Mint (NM or M-): Looks virtually unplayed, shiny, no marks under bright light, plays perfectly.
Very Good Plus (VG+): A few very light marks or light scuffs, may have occasional light surface noise, but still very clean and enjoyable.
Very Good (VG): More noticeable marks/scratches, some light surface noise or light pops possible, but still plays through without skipping.
Good (G) / Good Plus (G+): Lots of marks, plays with noticeable surface noise, possible light skips or repeats, but still playable.
Poor (P) / Fair (F): Severe scratches, bad noise, may skip heavily.
Cover Grading
Mint (M): Absolutely perfect, looks brand new, still sealed or unplayed.
Near Mint (NM): Nearly perfect, no obvious signs of wear, looks almost new.
Very Good Plus (VG+): Minor signs of wear (light ringwear, tiny creases, small writing), but still very clean.
Very Good (VG): Noticeable wear (ringwear, seam splits, writing, edge wear), but still respectable and intact.
Good (G) / Good Plus (G+): Heavy wear, seams may be split, heavy writing or tape, but cover is complete.
Poor (P) / Fair (F): Barely holding together, major damage.