Question: Diference between OST Promos, Recording Sessions, etc.

Hi Friends!!!

I have a question about the OST's.
In our days, we have a lot of diferents OSTs, I mean, first released a "NORMAL" OST with the basic music of the Film (but this almost always are a incompleted OST, we listen the music on the theater and then we listen the music on the OST and we say "heyyy, where are the track of the battle?" or something like that.)

Later, we have the surprise of the realese of the OST "Recording Sessions" with more music!!! (This kind of OST have music that are not used on the Film!!!, sometimes are excellent tracks!!! or alternate versions.)

Then, another surprise, a PROMO realese!!!, heyy another one???, then a lot of questions eg. (more music?, new version?, recopilation?, unrealesed tracks?, ...).

The question is... Someone have info about the diference of this OST's???.

I hope that you can help us to know more about this versions.
I just want info, because (in my case) always listed all the versions released of my favorites OSTs NORMAL, PROMO, RECORDING SESSIONS, COMPLETE, EXPANDED,..
Thanks to everyone!!!.

Jam it back in, in the dark.

Wow, excellent information...

So, We can say that all this material, is OFFICIAL, but the funtion on the market is diferent. I like a lor the "REcording Session" because we have a lot of extra music!!!.

There's nowhere I can't reach.