Alas, I typed a response but Broki caused the post to fail. I apologize if this is a duplicate response...

Yes, essentially what is happening is that you're creating micro-tears in your muscles, which your body then has to repair. If you're doing it correctly (i.e. not destroying your body), then those repairs get stronger each time... thus: gains. I'm sure one of my brothers and sisters can provide a much more accurate explanation, however.

I suggest that as you are starting out on the Iron Path you seek council from a certified personal trainer. These sages will ensure that you are not waylaid by Broki, and may save you much pain down the road.