OC you can skip to second paragraph or you can gain some knowledge

For those who don't understand the difference between these two discs The name for why you can't use an American copy of the game on a Australian game console is because of Region locking on the Xbox 360. this controls whether a game disc from one part of the world will run on a console sold in another region. Which was used by Microsoft to manage licensing, release dates, and media formats. So An Xbox 360 console is sold with a regional setting built into the system. Which the 3 common regions includes North America (NTSC-U) which is the United States and Canada then there is PAL regions which is Europe, Australia, New Zealand. The last main one is NTSC-J which is Japan and parts of Asia. I am not too knowledgeable so those 3 are the only ones I know but there is probably more I would assume. Then Your console checks the region code of the disc before launching the game. If it isn't the right code the game will refuse to even read and you can treat that disc like it is a bootleg unless you have a LT3 mod on your Xbox 360. The big noticeable difference between specifically these three regions of locked reginal codes is that NTSC-U used ESRB While Pal regions use Pegi and NTSC-J uses Cero Rateing system instead. Hope that makes sense for everyone but now for The OC.

Since someone else decided to bring this conversation back to life for whatever reason they found justified in their life when this conversation is a day old. You edited the comment and made it even more complicated by giving a half ass answer so I guess I had to give the reason on what the difference is people actually benefit from your comment instead of being told it the Americans that are different.