From Bulbapedia, the community-driven Pokémon encyclopedia.
Each item has a number used to identify it in any game. The following list enumerates them according to the way they are stored in any Generation II Game Boy Color game.
Items exclusive to Pokémon Crystal are Teru-samas in Pokémon Gold and Silver.
Index values 194 and 195 both contain an item named "TM04". The first index (194) is the real TM04. The second index (195) is a dummied-out debug item that shares the same name. It is stored in the Items Pocket, and has no "USE" option. When held by a Pokémon, its name is instead displayed as "Berry". It can be sold for 19660.