Cocoa Developer Documentation

Using Cocoa APIs

Cocoa Framework Reference
Cocoa has two core object frameworks: Foundation and Application Kit.

Foundation
Objective-C
Java A collection of "base" classes that specify fundamental object behavior. Foundation classes provide mechanisms for the deallocation, storage, notification, persistence, and distribution of objects.

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Application Kit
Objective-C
Java Provides a hierarchy of classes that support a graphical user interface, event handling, and general application behavior.

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Foundation Objective-C Java	A collection of "base" classes that specify fundamental object behavior. Foundation classes provide mechanisms for the deallocation, storage, notification, persistence, and distribution of objects.
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Application Kit Objective-C Java	Provides a hierarchy of classes that support a graphical user interface, event handling, and general application behavior.