ZFS has actually been around for quite some time. It was originally invented by Sun for use in Solaris. It has many advanced features like an improved RAID5 called RAIDZ. And though there's a bit of a learning curve it eliminates some complexity, like the need for a separate logical volume manager.
With the release of Ubuntu 20.04 it'll be possible to use it for your entire desktop system. But why would you want to use a "server" filesystem on your desktop PC? Well, in short, it makes upgrading your system bulletproof. Now every time you upgrade packages with apt it'll create a snapshot automagically. If something goes wrong there'll be a boot menu option that'll let you rollback your entire system to before the upgrade. It's fast, easy and you won't even know it happened, until you need it.
While technically it's still an experimental feature, I expect it'll become the default install option at some point in the future. If you haven't familiarized yourself with ZFS yet, now would be a good time to do so.
