It's a best trick to grasp some fundamentals of UIKit before rushing into ios development.
You will like to read my previous posts -Some important points About View Controller.Basically, loadView and viewDidload are the methods of UIViewController's lifecycle.I am going the explain the difference.
The code of UIKit will call loadView event when it needs to present that controller's view hierarchy on screen.
This method is used to create a view hierarchy programmatically, without using a nib.
UIViewController will never call loadView if you create View using nib.
If you are using storyboard, you can't use loadView.
In UIKit, viewDidLoad is called automatically when loadView completes all its tasks and the View is ready to display.That means all your IBOutlets are connected and you can make changes to labels, text fields, etc.
ViewDidLoad is used when you load your view from a XIB and want to perform any customization after launch
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