makeKeyAndVisible & makeKeyWindow - uiwindow in iphone

Question

In every application,

there is always written as [window makeKeyAndVisible];

What is mean by makeKey?

Answer 1

The key window is the window which will receive user interaction.

You might take a look at this:

http://developer.apple.com/mac/library/documentation/Cocoa/Conceptual/WinPanel/Concepts/ChangingMainKeyWindow.html

Answer 2

This means that this is the window that accepts keyboard input. This matches similar nomenclature on Mac OS X.