Lazy Instantiation: Add Subviews

1.    pushViewController: When you select an item from a tableViewController you can use a pushViewController to move to a nib file or a UIViewController.

a.  [self.navigationController pushViewController:viewController animated:YES];

2.  Lazy Instantiation: When a controller is alloc init it is lazily instantiated until you call the pushViewController method which instantiates the controller. This is important to know because properties cannot be set until the UIViewController has been instantiated.