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After 19 years stuck on the same major version number, Apple is finally unsticking MacOS. MacOS Big Sur, the first incarnation of its operating system to run on Apple's upcoming Arm-based Macs as well as its older Intel-based lineage, will get the version number 11.
"Big Sur is a huge step forward for the Mac. So much of the general architecture has improved that we are giving MacOS a new number," said Andreas Wendker, Apple's vice president for tools and frameworks engineering, on Monday. "Big Sur is MacOS version 11 because it really is a new Mac operating system all around."
He announced the new number at, Apple's conference for developers who build software for iPhones, iPads, Apple Watches, Apple TVs and Macs. The biggest news at the conference is that Apple will start moving its Mac family of personal computers away from Intel chips and instead build them around new versions of its own A series processors.
It's a major change for Apple, developers who write Mac software, and customers who buy the MacBooks, iMacs and Mac Pros. But Apple is betting the disruption will be worth it when it comes to performance, chip hardware features, battery life and the ability to get ahead of competitors by tightly integrating its hardware and software.
In Wendker's mind, the jump to version 11 is warranted by the support for Apple chips, a new user interface style for Big Sur and improvements to the Mac Catalyst tool that helps developers bring their iPad apps to MacOS.
Today's MacOS began as the NextStep operation system that Apple acquired along with Next's chief executive, Steve Jobs, who reclaimed control over Apple after his return. In 2001,, with the Roman numeral denoting a major shift from the earlier version 9.
Apple named its operating system versions after big cats like MacOS Lion and Snow Leopard, but later switched to scenic California references like High Sierra, Mojave and Big Sur. The numeric version numbers, though, steadily ticked up from 10.0 to today's 10.15, aka MacOS Catalina.