GameIDs

Nintendo console titles are identified by a 6 character identifier known as a GameID. There are 4 significant subsets in each GameID:

Subset #	Offset	Meaning
1	`X_____`	#System Code (1 character) – Identifies the system the title is for.
2	`_XX___`	Title Code (2 characters) – Identifies the title.
3	`___X__`	#Region Code (1 character) – Identifies the region the title is released in.
4	`____XX`	#Publisher Code (2 characters) – Identifies the publisher.

System Code

Code	System
C	Commodore 64
D	GameCube rerelease of Ocarina of Time Master Quest, as well as some GameCube Multi-Game Demo Disks.
E	Arcade or Neo Geo
F	NES
G	GameCube
H	Wii Channels
J	Super Nintendo
L	Sega Master System
M	Sega Genesis
N	Nintendo 64
P	TurboGrafx-16 and promotional GameCube
Q	TurboGrafx-16 CD
R	Older Wii
S	Newer Wii
W	WiiWare
X	MSX or WiiWare - Demos

Code	Region
A	System Wii Channels (i.e. Mii Channel)
B	WiiWare / Virtual Console titles
D	Germany (only if separate version)
E	USA
F	France (only if separate version)
I	Italian (only if separate version)
J	Japan
K	Korea
L	Japanese Import to Europe, Australia and other PAL regions
M	American Import to Europe, Australia and other PAL regions
N	Japanese Import to USA and other NTSC region
P	Europe and other PAL regions such as Australia
Q	Korea with Japanese language
R	Russian (only if separate version)
S	Spanish (only if separate version)
T	Korea with English language
U	WiiWare / Virtual Console titles
X	WiiWare / Virtual Console titles

There may be regional variations (e.g. Electronic Arts is 69 in EU/NA, but sometimes 13 in JP).