Proper noun
OS X
(computing, trademark) Former name of macOS; itself formerly known as Mac OS X.
Mac OS X Tiger will come out long before Longhorn. Steve Jobs
I think Leopard is a much better system [than Windows Vista] but OS X in some ways is actually worse than Windows to program for. Their file system is complete and utter crap, which is scary. Linus Torvalds
OS X is sweet: it's simple and intuitive, and I think GNOME shares a lot of values with it. Nat Friedman
I find if you're targeting Windows, Linux, and Mac OS X right from the start, your code will probably work anywhere else that you might try it later... Writing code that is cross-platform from the start requires more discipline, but I find it is worth the effort. Ryan C. Gordon