ZFS is one of the most sophisticated file systems nowadays and it outshines any other file system in terms of speed, performance and reliability. The speed at which data is processed on a server using ZFS is a lot higher, so not simply will any websites hosted on the hosting server be read and executed way quicker, but also backups could be created a lot quicker and more frequently without affecting the overall performance. Additionally, ZFS works with checksums - digital algorithms which are used to identify broken files. Anytime the file system identifies that there's a problem with a certain file, it fixes it using a good copy from another disk drive in the RAID. Both the checks and the repairs are executed right away, so the info saved on ZFS-based machines will be safe at all times due to the fact that it practically can't get corrupted. Another advantage of ZFS over other file systems is that there's no limit for the amount of files that could be saved inside a single account or on the hosting server as a whole.
