I have the privilege to do Solaris 11 tech-updates/demos at customers. It always amazes me how much they are amazed by ZFS. Don't get me wrong, ZFS is really cool. But it isn't exactly new technology, it's been around for a while now, the first implementations in 2003, included in Solaris 10 since S10 Update 2 in 2006. Everyone has heard about it being awesome, but every now and then I get the question for details: So tell me, what really makes ZFS so cool?
Let me tell you about it.
First and foremost: What were Sun's motivations to go and implement a new data management technology? Let's see.
So if next time anyone asks you about why ZFS is cool, tell them:
...and then of course we didn't yet talk about replication, shadow migration, shares, hierarchical filesystems, delegation, cache policies, dynamical property settings, dynamic striping and autoexpand, online versionupgrades, etc. Should you want me to write about those in a "Part II: a deeper dive" post - let me know in the comments.
 Although, who knows. Remember working with 180KB "large" floppies? Now my phone has a storage capacity 200.000 times larger than that. My current phone could replace the data storage needs of a smaller country back in the '80s. According to my quick exponential estimation, if data grows at this speed, then in around a 100 years we will need something beyond 128 bit filesystems :)