It's time to take a turn to some lighter fare, but to a subject that's near and dear to my heart. The fundamental UI component of a Cocoa app is the NSWindow, and there are many different ways to instantiate and manage them, but there is only one correct way: for each type of window, there should be a separate nib file, and a specialized NSWindowController subclass. I'll walk through what this means and how to do it, a topic suggested by reader Mike Shields.