macOS Big Sur (version 11) is the seventeenth major release of macOS, Apple Inc.'s operating system for Macintosh computers. It was announced at Apple's Worldwide Developers Conference (WWDC) on June 22, 2020, and was released to the public on November 12, 2020.
Big Sur is the successor to macOS Catalina, and was succeeded by macOS Monterey, which was released on October 25, 2021.
Most notably, macOS Big Sur features a user interface redesign that features new blurs to establish a visual hierarchy and also includes a revamp of the Time Machine backup mechanism, among other changes. It is also the first macOS version to support Macs with ARM-based processors. To mark the transition, the operating system's major version number was incremented, for the first time since 2001, from 10 to 11. The operating system is named after the coastal region of Big Sur in the Central Coast of California, continuing the naming trend of California locations that began with OS X Mavericks.
macOS Big Sur is the final version of macOS to support Macs with Nvidia graphics cards, specifically the 15-inch dual graphics Late 2013 and Mid 2014 MacBook Pro models, as it's successor, macOS Monterey drops support for those models.
Providing some indication as to how the pre-release operating system may have been viewed internally at Apple during its development cycle, documentation accompanying the initial beta release of macOS Big Sur referred to its version as "10.16", and when upgrading from prior versions of macOS using the Software Update mechanism to early beta releases, the version referred to was "10.16". An exception to this was the Developer Transition Kit, which always reported the system version as "11.0". macOS Big Sur started reporting the system version as "11.0" on all Macs as of the third beta release.
To maintain backwards compatibility, macOS Big Sur identified itself as 10.16 to software and in the browser user agent.
Unlike macOS Catalina, which supported every standard configuration Mac that Mojave supported, Big Sur drops support for various Macs released in 2012 and early 2013.