fedora core 28, ubuntu 18.04, raspbian etc.
To drift a bit off topic, I installed a recent version of android in a virtual machine,
(under ubuntu) just out of curiosity. I was a little surprised to see
it uses something called "toybox", much as my routers and modems use
"busybox". The layout of the filesystem is pretty unfamiliar to me.
The impression grows on me that, apart from desktops, the vast majority
of computers in the world run, at the bottom, a linux (or "unix-ish") kernel.