OS X OS X

OS X (pronounced /oʊˌɛsˈtɛn/, oh-ess-TEN; originally Mac OS X) is a series of Unix-based graphical interface operating systems (OS) developed and marketed by Apple Inc. It is designed to run on Macintosh computers, having been pre-installed on all Macs since 2002. Within the market of desktop, laptop and home computers, and by web usage, OS X is the second most widely used desktop OS after Windows.