At WWDC this year, Apple announced significant updates to their desktop and mobile operating systems in the form of macOS Mojave and iOS 12. The latter, which is set to bring numerous Siri improvements, Group Facetime and more, received a public beta yesterday. Today, macOS Mojave is following suit; the OS' open beta is available now.
For the unaware, Mojave is bringing a wide array of improvements and tweaks to the OS, including an improved "dark mode" for late-night work or play, a more attractive user interface, and Dynamic Desktop; a feature that changes the look of your desktop depending on the time of day.
Mojave is also bringing several formerly iOS-only apps, such as Memos, Stocks, News, and Home, to Mac devices. Despite these new feature similarities, though, Apple has no plans to merge iOS and macOS.
To download the update, you'll need to have an active Apple ID and you'll need to opt-in to the Apple Beta Software Program, but the process is otherwise relatively self-explanatory.