Mac OS X
From Mario Fan Games Galaxy Wiki
Mac OS X is series of operating system developed by Apple Computers. Based on Darwin, Mac OS X is successor of previous Mac OS 9. Not a lot of MFGGers use Mac OS X due to lack of support on the popular game developing software on MFGG - Game Maker. Recently, however, YoYo Games announced a Mac version of Game Maker and available for sale. Unlike the most popular operating system - Windows, Mac OS X is well simple and user friendly rather more professional.
Versions
The most recent version of Mac OS X is 10.7 Lion. Early in 2012, Apple announced that Mac OS X 10.8 is coming around later this year.