Release, Stable, Current, What's that ? What should you use while installing OpenBSD ?
First, you should know the FAQ uses the word flavors. I will use «version». Just less weird.
Release is the release published … when it's time. Roughly every six months, the firsts of may and november (until now). This version is fixed and documented. It's the version that was burned on CD (up to 6.0, OpenBSD sold CD for every Release). This is now stopped. It appears that burning CD was quite a huge workload (approximately a month on a cycle of six).
Stable is the Release version plus security patch.
If you follow me, you use Stable when installing or upgrading.
Current is the code currently in dev’ and test. It's what you get when you do:
Snapshots are versions of Current that are compiled every second week. If you install a snapshot, you actually install Current from max 15 days ago.
Thing is that OpenBSD is always a coherent system. So if you install Stable or Release 6.0 (for example), you get all the functions, all libraries in that on version. And all softwares have to be compiled along this version. Therefor if you use softwares packages from OpenBSD, they have to be taken from the 6.0 depot :
If you install a snapshot, you actually install Current from max’ 15 days ago. And you then have to build or install all your third-party softwares with this version. Third-party softwares in ports are also compiled and available in the project's FTP:
It becomes interesting if you regularly intall new softwares. If you installed a snapshot recently (the one from last month for example), then you installed Current… from one month ago. And you cannot be sure the software you want to install now will be compatible. You have to reinstall the whole system again. So reboot, install a new kernel then download all third-party softwares to finally be able to setup your new logiciel.
Any attempt to install a program too recent (from snapshot or from the ports) on a Release or Stable system shall fail, break the system or open a door to an infernal dimension. Opposite, if you are in Current and you try to setup a software from the previous version, you may end up very bad.
Let be clear : if, at any moment, you decide to install or switch your system to Current, you are then doomed to use and follow it up to the next Release. At this moment, the code shall get frozen and we will basically say :
Well, this is now Release X.Y.
At that point in time, you will be able to upgrade your Current from last month (or from two days ago) to the new Stable.
Your final word ?
If you use OpenBSD as a server, then install Release or Stable (to follow security patches). That way you avoid having to reboot every time (only when you have to have a new kernel).