https://www.theverge.com/2018/9/24/17895306/macos-mojave-10-14-release-date-download-features

MacOS version 10.14 — codenamed Mojave — is now available to download. The free update to Apple’s desktop operating system was first announced back in June with a number of new features including a dark mode, Stacks file organization, a redesigned Mac App Store, and enhanced screenshots. Although the software has been available in public beta for a few months now, this general release means most of the kinks and bugs should have been fixed.

In the grand scheme of things, Mojave is one of Apple’s more minor software updates. The headline feature is a new dark mode that makes your operating system look better even if it doesn’t technically add any new functionality. The new OS also adds support for Stacks, which can automatically group together files in order to keep your desktop tidy.