I've got a question about compatibility between projectors and carousels...like are there compatibility issues?

Do all carousels work on all slide projectors...was this something that was standardized? I have access to my parents' Kodak projector, but I remember seeing a lot of non-Kodak (i.e. non-yellow) carousel boxes at my wifes' grandparents' house. What's my chances of just having them work? Or do I need to find out the manufacturer of the carousels and find a projector what will work with them?

Any help is appreciated.

--Greg