If you're:
- A Linux user trying OpenBSD, FreeBSD or SmartOS - A Unix person wanting to use powershell - A Linux person moving between systemd/SysV init, or apt/yum OSs
Then is the the right document for you.
I submitted this a while back, but we've a couple more Operating Systems added and a lot of others expanded on since then.
It's on github too: https://github.com/mikemaccana/rosetta-stone