A Quick Tour of theFoundation Kit
you've already seen that Objective-C is a pretty nifty language, and we haven't even finished exploring all the features it has to offer. For now, we're going to take a quick side trip and have a look at Cocoa's Foundation framework. Although strictly part of Cocoa and not built in to Objective-C, the Foundation framework is so important that we thought it worth exploring in this book.
As you saw in Chapter 2, Cocoa is actually composed of two different frameworks: Foundation and Application Kit. The Application Kit has all the user interface objects and high-level classes. You'll get a taste of the AppKit (as the cool kids call it) in Chapter 14.
Cocoa's Foundation framework has a bunch of useful ...