Freon is a brand name. The correct term is refrigerant and there are quite a few types such as R-22, R-12, 404a, 409, RB-276, 134a, MP-66, etc. Or more specifically, R-22 is monochlorodifluoromethane and R-12 is dichlorodifluoromethane. Those are the only two I know by memory.
Eh, it's just one of those things. Didn't mean to make such a big deal of it.