Objective-C is the typical programming language that Cocoa applications and frameworks are written in. Created by Brad Cox in the early 80s, the language is often likened to SmallTalk for its object oriented stance, and highly dynamic and introspective runtime.

More information:
http://developer.apple.com/documentation/Cocoa/Conceptual/ObjectiveC/∞
http://en.wikipedia.org/wiki/Objective-C∞

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