macOS: the power of Unix serving the Apple ecosystem

macOS (formerly Mac OS X, then OS X) is the operating system developed by Apple for its Mac computers. Announced in 1998 and marketed from 2001, it is one of the pillars of the Apple ecosystem alongside iOS, iPadOS, watchOS, tvOS, visionOS and audioOS.
The most recent version, macOS Tahoe (version 26), was launched on 15 September 2025 for the general public.

From the successor of Mac OS Classic, macOS is based on a Unix-type architecture, offering stability, security and efficiency recognized in both the professional world and the general public. The system derives from the technologies developed by NeXT, the company founded by Steve Jobs in the 1980s, acquired by Apple in 1997.
The first iteration, Mac OS X Server 1.0, was released in 1999, followed by the general public version in March 2001.

Since Mac OS X 10.5 Leopard, macOS has received the UNIX 03 certification from The Open Group, first for Macs with Intel processor, then also for those equipped with Apple Silicon chips from macOS 11 (Big Sur).

Designed to take advantage of Apple hardware, macOS offers unique hardware and software integration, an elegant and intuitive interface, as well as close compatibility with other devices of the brand thanks to technologies such as Handoff, AirDrop, or Universal Control.

The server version of macOS shares the same architectural basis as the general public version, while offering specialized tools for network administration, messaging management and file services. Since Mac OS X 10.7 (Lion), this server version is distributed as a downloadable extension from the Mac App Store, simplifying its deployment.

In 2016, on the occasion of the WWDC, Apple formalized the return to a unified nomenclature: OS X became macOS, with the release of macOS Sierra (10.12).
Today, macOS continues its evolution by combining Unix heritage, Apple design and continuous innovation, to offer a computer experience that is both efficient, fluid and intuitive.