So first things first, which Macs will be compatible with macOS Sierra? What hardware will run the new operating system and let you use all those features like Siri, Continuity Clipboard, etc.? No doubt that newer Macs will easily support the new system, but older machines are getting excluded, especially those made before 2009. It is going to be available as a free download for all compatible Mac computers this coming fall. The upcoming version of Mac system software has a name macOS Sierra, and is versioned as Mac OS X 10.12.
