Haven't seen this mentioned already, but as we know, sometimes there is more than one edition of a game released.

On occasion you will have the "Gold" Edition, or "Special" edition (or whatever edition name they decide to give this).

In most cases the main game is on the Blu-Ray disc, but the extra content is a DLC.

So how can we back these up, is this possible?

Also, if you have a backup and try to reinstall it? (Say for example you format your HD and then try to re-use the DLC, will this still be successful?)