What order should I play them in?

[second.exodous]

I was wondering if anyone that has played through all the Penumbra games would give me a suggestion of what order to play them in. I'm guessing Requiem then Black Plague then Overture. Is that correct? or is it better to play them out of order.

Also, if I buy them could I get them both in OSX and Linux or just one or the other?

[Yuhaney]

If you play them in that order, it's totally upside down.

Overture, Black Plague, Requiem. That is the correct order...