Ryan Faas, writing for Computerworld:

Although OS X is now an integral part of the Mac experience, it represented a big gamble for Apple when the first general release version — code-named Cheetah — arrived on March 24, 2001. It was also a gamble that Apple had little choice in making — and one that has paid off in the 15 years since, becoming, directly and indirectly, one of the critical factors in Apple’s success.

The biggest benefit to Apple of the NeXT Acquisition was bring back Steve Jobs. But the Unix underpinnings that became OS X and the programming paradigm that came along with it were also critical. This post walks through through the history of the birth of OS X. Fascinating.