It’s a program certainly, but “just a program” is a bit misleading because it places it on the same footing as Doom or cat or an Arduino project. Linux is a ring 0 program, which processors give unique treatment.

Zaphod’s just zis guy, you know?

Well, the kernel is not “just a program” in that it is not like the other programs on your system. If it was, you would “just” run it in your shell. The kernel cannot run this way of course because it is not a user mode program.

That said, if course the kernel is a program in the sense that it is a set of machine instructions that make the hardware do what you want.

And the kernel is designed to talk to hardware and other programs—to be the bridge between the two. It is not something an end-user interacts with directly.

Thanks op this is a great article. Having compiled kernels since 2.4 or thenabouts, it's a great topic and I never really thought of it as just another program. Neat stuff!

On my arch install, all I have is vmlinuz-linux under /boot. How come there's no further information appended like in the article?

Yeah it's just as simple as the calculator program I copy pasted in highschool computer class.