macOS Sierra is version 10.12 of Apple Computer’s Mac OS X operating system for Macintosh desktop, laptop and server computers, and it serves as the successor to Mac OS X El Capitan.
Apple tweaked the naming scheme of its flagship OS with the macOS Sierra release, dropping the Mac OS X moniker for the shorter and simpler “macOS,” which also fits better with the company’s full lineup of operating systems that includes iOS, watchOS and tvOS.
macOS Sierra Officially Arrives in Fall 2016
macOS Sierra was introduced at Apple’s 2016 Worldwide Developers Conference (WWDC) in early June 2016 alongside iOS 10, with official availability for both operating systems expected in the fall.
macOS Sierra serves as the twelfth update in the macOS / Mac OS X line of operating system updates, following earlier updates for the operating system: Cheetah (v10.0), Puma (v10.1), Jaguar (v10.2), Panther (v10.3), Tiger (v10.4), Leopard (v10.5), Snow Leopard (v10.6), Lion (v10.7), Mountain Lion (v10.8),…