All the major OS releases come with some major improvements clubbed with minor improvements made to the OS, which directly or indirectly improve the usability of the OS. Apple’s Mac OSes are the ones that are most frequently updated and Apple has released 22 major OSes to develop their Mac computers and provide users with the best computing experience. Though the OS is a bit non-user friendly, Apple has been trying to make the OS more user friendly by making the OS simpler. Mac OSes are sophisticated and complex making them powerful and reliable.