OS X is Apple’s operating system that runs on Macintosh computers.

It was called “Mac OS X” until version OS X 10.8, when Apple dropped “Mac” from the name.

OS X was originally built from NeXTSTEP, an operating system designed by NeXT, which Apple acquired when Steve Jobs returned to Apple in 1997.

What is the latest version of OS X?

Mac OS X & macOS version code names

• OS X 10.9 Mavericks (Cabernet) – 22 October 2013.
• OS X 10.10: Yosemite (Syrah) – 16 October 2014.
• OS X 10.11: El Capitan (Gala) – 30 September 2015.
• macOS 10.12: Sierra (Fuji) – 20 September 2016.
• macOS 10.13: High Sierra (Lobo) – 25 September 2017.
• macOS 10.14: Mojave (Liberty) – 24 September 2018.

What app is OS X?

The App Store is a digital distribution platform for macOS apps, created by Apple Inc. This platform was announced on October 20, 2010, at Apple’s “Back to the Mac” event.