MacOS with the previous name OS X or earlier Mac OS is Apple’s exclusive Desktop operating system, which macOS High Sierra was the latest version of the operating system for PCs and Macs.
MacOS Mojave is the new Apple desktop operating system which features a dark-skinned theme on the system-level, which gives the interface a more attractive appearance with black or gray elements. The dark theme is one of the most awaited features that macOS users are looking to add.