Ry's Objective-C Tutorial

Objective-C is one of the native programming languages for Apple’s iOS and OS X operating systems. It’s a compiled, general-purpose language capable of building everything from command-line utilities to animated GUIs to domain-specific libraries. It also provides many tools for maintaining large, scalable frameworks.
Ry's Objective-C Tutorial serves as both a concise quick reference and a comprehensive introduction for newcomers to the language. It walks through each language feature step-by-step, explaining complex programming concepts via hands-on examples. By the end of the tutorial, you'll understand basic language constructs, important memory-management techniques, and many of the built-in Objective-C data types like NSNumber, NSArray, and NSDate.
While it is a friendly guide to Objective-C, this tutorial focuses solely on the programming language, rather than on iOS or Mac App development. You won't walk away with the ability to create your own iPad apps, but you will be incredibly prepared to continue down that path. Also, be sure to check out Ry's Cocoa Tutorial if you're interested in Mac App development.