Looking to understand the iOS UIViewController lifecycle

Question

Could you explain me the correct manner to manage the UIViewController lifecycle?

In particular, I would like to know how to use Initialize

Answer 1

Haider's answer is correct for pre-iOS 6. However, as of iOS 6 viewDidUnload and viewWillUnload are never called. The docs state: "Views are no longer purged under low-memory conditions and so this method is never called."