Graham Lee on the history of Cocoa:
First there came message-passing object oriented programming, in the form of Smalltalk. Well, not first, I mean first there was Simula 67, and there were even things before that but every story has to start somewhere. In 1983 Brad Cox added Smalltalk messaging to the C language to create the Object-Oriented pre-compiler. In his work with Tom Love at Productivity Products International, this eventually became Objective-C.
Graham goes on to provide information on a series of books, all leading to what we now know as Cocoa.
Happy Birthday Cocoa.