On my long journey of computers with UNIX and UNIX-like operating systems, FreeBSD is the one constant over time. Today FreeBSD is celebrating 30 years. You can scroll through the 30 Year Timeline to get a feel for the pre-cursors to FreeBSD and what the project has accomplished in this time.
When I first found FreeBSD I thought of it as a hobby project to tinker with on spare hardware. In order to learn it better, I bought and read "the book" about it, "The Design and Implementation of the 4.4BSD Operating System". It's a thick book full of technical details, implementation decisions, and references to code to see how features are implmented. In other words, it's a glorious book.
A few of my early screeshots show my computer running FreeBSD.
Over the years, I've tried many, many different operating systems, but I still come back to FreeBSD as "home". Over the years, FreeBSD and OpenBSD became my preferred server OS. They're simple, very stable, and can run for months to years without issue.
I subscribed to FreeBSD Journal magazine, went to a few BSDcons (BSD conferences) and even hired BSD developers at various companies to improve the system, make new hardware work, and give back to FreeBSD. For a retro treat, visit BSDCon from 2000. At work, I purposely chose vendors that used and supported BSD-based solutions (firewalls, NAS, load balancers, etc).
All in all, BSD is great and I'm going to continue to do what I can do make sure it lasts another 30 years.