[kjam22]

Let me ask you two simple questions. 1) Was it at some time a theory that a rocket could orbit the earth? And 2) Is it now a proven fact that a rocket can orbit the earth?

I'm completely serious... if you can't get past this understanding..... then you do need to study more... and you need to study more than just science.

[Junior]

I think the orbit thingy was basically mathematics, not theory. However, let's put together some definitions. Evolution is a fact, for example. We know that organisms change from generation to generation. Nothing special there. Evolution, the theory, attempts to explain why evolution, the fact, occurs. In your rocket example the rocket orbits (fact); if there is a rocket-orbit theory it attempts to explain why the rocket orbits.