well if you have ever seen a torrent or something on the internet for an album that has not yet been released, you will probably see that in parenthesis it may either say "Promo" or "Advance" and i was just wondering what that means. Is there something different about those particular copies as to if you were to buy the album on/after it's release date?
I think promos are sent out mainly to journalists for review etc, advance copies are just pre-ordered copies.

I think.
According to BS statistics, 92% of teens have moved on to rap. If you're among the 8% who doesn't consider rap to be real music, donate your brains, as you clearly aren't using them.