Aah, the h1 mystery… Nobody knows. I wonder if Virtual Bomberman was h1?
Game IDs are unique and can be used to identify a game. The japanese version of Galactic Pinball has the serial VUE-VGPJ-JPN for example:
VUE – System
V – “Virtual Boy?” Not sure, every VB serial has a V here
GP – Game ID
J – In-game Language of the game. J for Japanese in this case.
JPN – Region the game was released in. JPN for Japan in this case.