This is a brief explanation of how I grade my cards:

MT (Mint)

A beautiful card, centering is 50/50 with all sharp corners. No minor wear on any part of the card. Card is in focus and free of print lines.

NM (Near Mint)

A very nice card, centering is 75/25 or better with sharp corners. Could have minor chipping on corners and edges. Card is in focus and free of print lines.

EXMT (Excellent-Mint)

Still a nice high grade card, centering is 80/20 or better. Corners have minor to moderate wear, but are still relatively sharp and card has overall nice appearance.

EX (Excellent)

A solid mid-grade card, centering must be 90/10 or better. Corners can have moderate wear, but no rounding, creasing, or major problems on this card.

VGEX (Very Good-Excellent)

The nicest of the low-grade cards. Card cannot be miss-cut, but can be off center. The corners can be slightly rounded. No major creases but could have a minor crease, or wrinkle. No intentional damage can be on this Card (writing or staining).

VG (Very Good)

Still a Decent Low Grade card. No intentional Damage on the card. There can be a major crease or multiple small creases, but there is not a crease that destroys the eye appeal of the card. Card can be miss-cut.

GD (Good)

There may be back damage, Multiple creasing, markings on the front or back of the card. The card is intact, but by no means an attractive card.

PR (Poor)

This is the lowest grade. This is just to say I have the card. Can have part of the card missing, writing, major creases, etc..