macOS Big Sur is also officially macOS 11
Apple has bid farewell to macOS X with the launch of macOS Big Sur. It ends the run of macOS X releases dating back 19 years to March 24, 2001 when it shipped on the famous Bondi Blue iMac. Originally called Mac OS X when it launched, then later OS X, the last official version of the operating system, Catalina, bows out on version 10.15. macOS Big Sur is officially macOS Version 11.0.
Of course, macOS Big Sur is the very first release of Apple’s operating system to run on Apple’s own ARM-based silicon, which is likely the main reason for Apple to consider it a major overhaul -- if not dramatically different on top, it has been completely rearchitected under the hood. The new operating system also picks up a redesigned user interface that uses translucency and light along with more intuitive navigation symbols. Newly redesigned app icons also bring it into line with Apple’s iOS and iPadOS operating systems.
With iOS and iPadOS apps now able to run natively on Apple’s custom ARM-based silicon (the same silicon that powers its iPhone and iPads), the changes create a more consistent look and feel across Apple’s product line. As iOS and iPadOS have become increasingly the biggest sellers in Apple’s product portfolio, Apple’s mobile OSes have started to more strongly influence not only its look, but the newer features introduced to it as well. So much so, that now macOS even runs on the same silicon as Apple’s mobile devices.