APFS also acknowledges the advances in technology in the nearly two decades since Apple's current file system, HFS+, hit the scene. It's optimized for flash storage, uses extremely fine-grained time stamps (down to the nanosecond) and supports a whopping 9 quintillion files on a single volume. You'll also see "snapshots" (read-only instances of the file system) that make Time Machine-style backups easier.

The file system is available to developers in preview form right now, and it should launch in earnest in 2017. However, unlike the usual operating system previews, you don't even dare try this unless you're writing apps where it'd be a factor. The prerelease APFS can't be used to boot a device and doesn't support many Mac staples, such as Fusion Drives or Time Machine. There's no certainty that the data you put on a drive now will be readable by later versions of APFS, for that matter. Nonetheless, its very existence is noteworthy: It'll likely dictate the features of Apple gadgets for years to come.

Get all the latest news from WWDC 2016 here!