Does it just mean that you can have a license in your home state, and a temporary license in another state?

Or does it mean that you don't have to re-test or go to school if you move to a reciprocal state (that will license you)?

I'm looking into this myself. I'm licensed in CA and am thinking of moving to GA in a year or two. It sounds like I just have to pay a fee, take a test, and then I'll have a license to practice in GA rather than go through hours of classes first.

In most cases what that means is you have to pass an exam on that states laws in order to be licensed in that state. Not all states have reciprocity. Some you have to complete all the educational requirements and pass a test. So no there is no temporary licensing.