if you wanna learn how a basic engine works, both rotary and internal combustion, go to
www.howstuffworks.com
Here is the link for the internal combustion engine, and
here is the link for the rotary engine. They are both complete with flash animations and detailed explanations........feel free to explore other stuff in their auto section, you can learn a lot about what goes on inside your car before you dive in yourself and start working on it...........but when you do decide to do that, definitely buy a haynes manual, they are lifesavers sometimes.