No, it’s not a joke. The name really is High Sierra. It’s likely due to the fact that there isn’t a ton of huge changes enough to warrant a whole new name.
One thing that we all loved was the Safari now blocks video that plays automatically. That means no more being startled and searching for a video that plays when you open a page. There’s also a ton of changes to the Photos app. We find some better organizational and editing tools.
The mail app see some improvements, such as taking up less space on the disk, intelligent tracking prevention, and full screen split view.
Under the hood, this version of macOS now uses Apple’s new file system found in iOS. It is supposedly faster, safer and more reliable.
This version of macOS is available to developers today. It will launch to the public this fall.