The difference between Mitosis and Meiosis?

I'm taking General Biology. I have a vague background on biology so basically this is all new to me. We learned mitosis and meiosis, and we're going to have a test on it soon. While I know the general points, I want to know it better. Why does meiosis have two parts ? (i.e. metaphase I, metaphase II). I'm better at mitosis, but I need more information or help on meiosis. Thanls ;)