Apple today seeded the second public beta of an upcoming macOS High Sierra update to public beta testers, two weeks after releasing the first public beta. The second public beta of macOS High Sierra corresponds with the third developer beta, provided to developers earlier this week.

Beta testers who have signed up for Apple's beta testing program are able to download the second macOS High Sierra beta through the Software Update mechanism in the Mac App Store after the proper profile has been installed.

Those who want to be a part of Apple's beta testing program can sign up to participate through the beta testing website , which gives users access to iOS, macOS, and tvOS betas. For instructions on how to install the public beta, check out our how to , and make sure to make a backup before giving the software a try. Don't install the beta on a main machine, as betas are notoriously unstable. High Sierra runs on all machines that support Sierra.

The macOS High Sierra update is designed to improve and refine the existing macOS Sierra operating system. Along with a new, more efficient file system (APFS) designed for modern storage, the update introduces Metal 2, the next-generation version of Apple's Metal graphics API with support for machine learning, external GPUs, and VR content creation.

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High Efficiency Video Encoding (HEVC aka H.265) is coming in High Sierra, and many of the existing apps are being updated. Photos features a new persistent side view and editing tools for Curves, Selective Color, and Live Photos, while Siri is gaining a more natural voice and support for more music-related commands.

Safari offers a new autoplay blocking feature for videos and Intelligent Tracking Prevention to protect your privacy, while Mail storage is being optimized to take up 35 percent less space. iMessages can now be stored in iCloud, and there are new iCloud Drive file sharing options and new iCloud storage family plans.

For a full overview of the new features you can expect to see when macOS High Sierra is released in the fall, make sure to check out our full macOS High Sierra roundup.