Updated at: Apr 19, 2026
macOS is Apple's Operating System for their computers: it's for Macbooks, Macbook Pros and Desktops. It's a multi user, multi-tasking, modern operating system. It's based on the UNIX operating system and provides a very attractive and intuitive user interface.
| Platform | Version Number | Release Date |
|---|---|---|
| macOS | 15.7.5 | 2026-03-25 |
macOS used to be called "OS X" - Apple changed the name to macOS with the release of macOS "Sierra" - version 10.12 - in September 2016. The name change brings it more in line with the naming conventions of other Apple products: namely "iOS" - the operating system for iPhones and iPads.
OS X was first released in March 2001 (code name: "Cheetah"). Apple then went on to release new and improved versions of OS X every one to two years. At first their code names for OS X were "big cats" (Puma, Jaguar, Panther, Tiger, Lion etc), from version 10.9 onwards they are code named after locations in California (Sierra, Mojave, Catalina etc).
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