Polaroid One Step 600 Instant Camera Film Great Fun! What Type Of Film Can I Use For A Polaroid One Step Camera?

What type of film can I use for a Polaroid One Step camera? - polaroid one step 600 instant camera film great fun!

I've recently bought an old Polaroid instant camera (Polaroid Land Camera One Step SX-70). I know I can explicitly use the film 600 - but that means that you are getting other "can 600-series on" Films such as 667 or 669?
And if so, everyone knows what is the difference?

Link to a picture of a special kind of camera: http://i22.ebayimg.com/08/i/000/f5/4d/c146_1.JPG