What is Superview in iOS? (Beginner's concept brief version)

Wen/Sima Jian (book author)/articles have been censored
The original link: http://www.jianshu.com/p/8537dac37852 copyright belongs to the author, reprint please contact the author to obtain authorization, and Mark "Jane book author".

In the iphone's view, is actually one view, a layer of view above a layer of view, a view above a group of views, even UIWindow is a view, on the Internet to find a picture can explain the problem:

What we can see is a view, and we can manipulate it because both Uicontroller and UIView are subclasses of Uiresponder. And Superview's concept is better understood, the view can be placed on the control, then this view is the Superview of these controls. And the UIWindow can be stacked layer after layer of View,uiwindow is the superview of these view.

What is Superview in iOS? (Beginner's concept brief version)