If your Mac isn't compatible with OS X El Capitan, the installer will let you know. To find your Mac model, memory, storage space, and macOS version, choose About This Mac from the Apple menu. Mac Pro introduced in early 2008 or later Xserve models introduced in early 2009. Mac OS X 10.0 was released on Mafor a price of US$129. Mac OS X version 10.0 (code named Cheetah) is the first major release of Mac OS X and the first version of macOS 10 (until 11.0 Big Sur) (renamed OS X in 2012 and macOS in 2016), Apple's desktop and server operating system.
