GID

The GID stands for game id or game object id. It uniquely identifies each and every dynamic object (NPC, monster, player, item, skill unit) inside the game. For the players a GID is their account id, for all other objects it is a server-generated id, that changes each time the object is created.

You can view the id in-game by right-clicking on a object, when your account has enabled game master menu.