compatable .tib files for PC and Mac?

I've always had PCs but I'm now considering buying my first laptop- a Mac.

Since I've been thinking about this- I finally become aware that you can install ATI on both Macs and PCs. So, are the .tib files compatible? That is, I realize I wouldn't be able to boot up a PC or Mac if the the recovery boot media was from the other type of computer- but let's say that I want to port all my MS Office files (thousands) to my Mac. I suppose I could simply copy the files over my home network from one to the other. But, I'm curious if the Mac could read the .tib file produced on the PC? Or vice-versa? In most cases, I'd have the .tib files on an external drive, which I presume could be read by both types of computers.

Joe